FOUS30 KWBC 172013
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
413 PM EDT Wed Jun 17 2026

Day 1
Valid 01Z Wed Jun 17 2026 - 12Z Thu Jun 18 2026

...THERE ARE MODERATE RISKS FOR EXCESSIVE RAINFALL FOR PORTIONS OF ILLINOIS/INDIANA AS WELL AS THE MISSISSIPPI DELTA...

...1600 UTC Update...

The Moderate Risk in the Midwest has been shifted south based on
current observational trends and the latest 12Z hi-res guidance
with regards to an ongoing MCS over northern Illinois. This will
likely limit the northward progression of the warm front/effective
outflow into the afternoon hours bringing the greatest threat for
heavy rainfall/flash flooding along a west-northwest to east-
southeast axis through central Illinois into central Indiana. This
includes both the more intense storms on the southern/southwest end
of the ongoing MCS able to tap into greater moisture/instability
along the warm front as well as for additional storm development
that will focus along the warm front/effective outflow. Repeated development/potential training of robust, heavy rainfall producing
storms (rainfall rates ~ 2 inches/hour) leading to totals of 3-5",
locally as high as 6-7", will pose a threat for scattered to
widespread incidents of flash flooding.

Further south, the Moderate/Slight Risk areas have also been
minimally adjusted based on the latest 12Z guidance along and east
of the track of what is now Tropical Storm Arthur. Plentiful
tropical moisture will support additional rainfall totals of 3-5"
with localized amounts as high as 6-10". The highest totals look to
focus along a corridor within southeastern Louisiana generally
between Baton Rouge and New Orleans where the greatest threat for
more widespread instances of flash flooding will exist.

Putnam

Southwest United States...
Another round of isolated late day and evening thunderstorms
capable of producing locally heavy rainfall is possible. Given low
level moisture being capped by broad but fairly weak subsidence
associated with an upper high...the expectation is for any
convection to develop over or near the complex terrain which would
act as localized heat sources. As such...loss of daytime heating
should lead to fairly quick dissipation following sunset.

Bann

...Previous Discussion...

...Chicagoland...

A potent low racing out of the Plains and across the Great Lakes
today will run into an increasingly moist air mass in place ahead
of the low over the Midwest. As the low approaches the Chicagoland
region late morning, convection will break out along the low's warm
front extending east of the low center. The initial hit of rain
with the warm front is unlikely to feature too much heavy rain,
though embedded elevated convection could make for brief heavier
downpours. Immediately behind the warm front, however, a surge of
moisture and instability will fuel backbuilding thunderstorms
during the afternoon ahead of a strong cold front trailing behind
the low. These storms are progged by many of the CAMs to generate
into several broken lines of storms as they cross northern Illinois
and into northern Indiana and southern Michigan through the late afternoon/early evening. These storms will have ample forcing
allowing them to organize into severe clusters of storms. They are
likely to produce locally heavy rainfall rates of up to 2 inches
per hour where they backbuild. However, since the series of line
segments will be sufficiently separated by much lighter or no rain,
it seems any flash flooding that results from these storms will be
more localized and less widespread. Further, as mentioned, the
storms will be racing very quickly, likely moving at 40+ mph. This
will greatly reduce the time any one area sees heavy rain, but
since the lines are expected to align parallel to the windflow,
those areas may see a bit longer time of heavy rainfall.
Hydrologically, the Chicagoland area has seen several bouts of
heavy rain in recent weeks that have left the soils above normal
for moisture content as well as prone to flash flooding with
sufficiently heavy rain. Of course, the large urban area of Chicago
will also help to worsen any flash flooding that develops, so in
those local areas where heavy rain overlaps with urban areas,
locally considerable flash flooding is possible. Further east into
Indiana, eastern Michigan, and eventually northwestern Ohio, the
lines of storms this evening should align with the cold front and
largely orthogonal to the flow. This should lower the flash
flooding risk in these areas, despite similarly favorable
hydrology.

...Mississippi Delta...

The moisture plume of Potential Tropical Cyclone 1 (PTC1) will
continue to slowly advect northeast across the northwestern Gulf
and into southern Louisiana today into tonight. For much of the
day, the heaviest rains will remain offshore, and except for
occasional showers and an isolated storm or 2, much of the area
should not contend with much heavy rain. That changes tonight as
the center of circulation of what may be Tropical Storm Arthur
moves ashore near the TX/LA border. All of the deep moisture will
be east of the center of circulation, so that will direct the
fire-hose of heavy rain into south-central Louisiana, from the
Abbeville/New Iberia area northeast near Baton Rouge and into
southern Mississippi after midnight. By that point, the diurnal
strengthening of the nocturnal jet will function as the the primary
driver of heavy rain as northeastward moving storms backbuild into
the jet. The area from around Baton Rouge northeast to the north of
Lake Pontchartrain and into far southern Mississippi is likely to
be the corridor with the heaviest rain.
There is considerable uncertainty first of the eastern extent of
the axis of heaviest rain, particularly in relation to the New
Orleans Metro. For now most of the guidance makes a very tight
gradient of moisture, which most of the city remains on the drier
side of. However, this axis of heaviest rain has been shifting
east from model run to model run over the last couple days, which
any further eastward drift would bring New Orleans right into the
corridor of multiple-inch per hour rainfall for multiple hours.
Regardless, even if New Orleans misses out on the heaviest
rainfall, feeder bands of showers and storms could still cause
localized flash flooding in the city. Thus, the Moderate Risk
remains largely unchanged and includes New Orleans. More than a
couple CAMs do bring strong cells over the city, which would very
quickly lead to flooding problems.

Wegman
=20

Day 2
Valid 12Z Thu Jun 18 2026 - 12Z Fri Jun 19 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE SOUTHEAST...

...2030 UTC Update...

Only a few minor areal adjustments were made to the inherited risk
areas with the prior forecast reasoning remaining on track for the
Southeast, Ohio/Tennessee Valleys, and areas further west into Arkansas/Oklahoma. The most notable was to expand the Moderate Risk
back northeast a bit to include metro Atlanta. While rain totals
in the hi-res guidance tend to be lower overall further north than
the noted shift south overnight, the expected track of the
remnants of what is now Tropical Storm Arthur will pass very close
to the region. This will bring intense low-level flow (50 kts+) and
high PWATs (2-3") northward which could lead to some more intense
rainfall and heavier totals than currently depicted in the
guidance, and at least some of the hi-res runs showed the potential
for totals of 3-4". The urban area will also remain more sensitive
compared to elsewhere even if totals do not match some of the
higher end amounts anticipated further south. Otherwise, the rest
of the region was left mostly untouched. The latest 12Z hi-res
guidance depicted the potential for significant rainfall totals
particularly across southern portions of the Moderate Risk area
(southern Alabama into the western FLorida Panhandle), with areal
average totals in the 4-5" range and locally higher totals as much
as 6-10", more than sufficient for scattered to widespread flash
flooding. The HREF and RRFS both showed moderate probabilities
(40-60%) for totals of greater than 8 inches. One other adjustment
was to extend the Marginal Risk further westward across the
southern Plains into portions of the Texas Panhandle and eastern
New Mexico where afternoon/evening storms ahead of a sagging cold
front could bring a couple heavier downpours and possibly some
isolated flooding concerns within cities.

Putnam

...Previous Discussion...

...Southeast...

Very heavy rain associated with what will be the remnants of PTC1
will be ongoing at the start of the period over most of southern
Mississippi and likely extending into southwestern Alabama. These
storms will be fueled by a strong low level jet pumping deep
tropical moisture into a corridor that covers much of the Moderate
Risk area. By around midday, the rapidly increasing instability and
the typical weakening of the low level jet will allow the
widespread convection to transition into training lines of storms
that track east with time, as the line gradually drifts south
towards the greatest instability and moisture source that is the
Gulf. Thus, the greatest focus of heaviest rain now appears to set
up from southeastern Mississippi east across the southern tier of
Alabama and far western Georgia. 3+ inch/hour rainfall rates from
individual storms will combine with multiple hours of rain as the
storms train along the east-west oriented lines. Storm total
rainfall for the day could easily exceed 8 inches in spots. Mobile,
AL will be the biggest city in the crosshairs of the heaviest
rainfall.

With this rather dramatic southward shift in the guidance of where
the heaviest rainfall totals are expected, the Moderate Risk
inherited was trimmed significantly on the north side, while
expanded across southeast Alabama, the western Florida Panhandle,
and far southwestern Georgia. The Moderate Risk was downgraded out
of both the Birmingham and Atlanta metros as those areas see
leftover heavy rains from the much more potent and heavy rain
producing storms much closer to the Gulf Coast. Nonetheless,
periodic convection and a long duration of light to moderate rain
is still expected over those metros, so the higher-end Slight
remains in effect. Convective coverage greatly decreases Thursday
night over all of the Southeast, but isolated to widely scattered
storms could persist through the night in some areas.

...Ohio/Tennessee Valleys...

Further north from the Gulf Coast along the Ohio and Tennessee
Valleys, a cold front will start the day following roughly parallel
to the Ohio River. The front will slowly sink southward over
Kentucky through the day. Meanwhile, daytime heating and
unidirectional southwesterly flow ahead of the front is expected to
generate a long line of storms. The storms will be training and
backbuilding along the KY/TN border and extending into West
Virginia. Guidance has shifted a bit further south, especially with
the western end of the line, so the higher-end Slight now follows
the entire length of the KY/TN border, and now includes Nashville,
while the Ohio River has largely been removed from the risk area.
With nightfall and the loss of daytime heating, the flash flooding
risk from storms will also diminish.

...Arkansas/Oklahoma...

On Thursday night, the westernmost extension of the low-level jet
over Texas will run into the same stalled out front that extends
east into Kentucky. This clash of air masses is likely to result in
the development of an MCS over eastern Oklahoma, which will then
propagate southeastward into western Arkansas. Here too the soils
are wetter than normal from multiple bouts of heavy rain in recent
weeks, so a Slight Risk remains in place over the area with few
changes.

Wegman
=20

Day 3
Valid 12Z Fri Jun 19 2026 - 12Z Sat Jun 20 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR MUCH OF
SOUTHERN ALABAMA...

...2030 UTC Update...

Only very minimal areal changes were made to the inherited risk
areas as the prior forecast is consistent with the latest 00/12Z
guidance for both the Southeast as well as central/western Texas.
Rainfall totals across the Moderate/Slight Risk areas in the
Southeast will likely be down overall compared to Thursday as the
remnants of what is now Tropical Storm Arthur depart the region.
However, the region will remain much more susceptible to
additional rainfall given the amounts expected Thursday,
particularly for those in the Moderate Risk area across southern
Alabama into the Florida Panhandle which overlaps Thursday's risk
area. It likely will not take much to lead to additional flash
flooding as well as exacerbate any ongoing flooding.

Putnam

...Previous Discussion...

...Southeast...

Any lull in heavy rainfall across southern Alabama from Thursday
night behind the precipitation shield associated with the remnants
of Potential Tropical Cyclone 1 will end in a hurry Friday morning
as the cold front over the Tennessee Valley continues to press
southward and runs into the ongoing southerly flow and low-level
jet of deep tropical moisture from off the Gulf. The clash of these
air masses looks to maximize over southern Alabama, where storms
are likely to continue in some form or fashion for much of the day
Friday. Assuming the multiple inches of rain from Thursday occurs
in these same areas, the slightly lower storm total rain on Friday
will make little difference for the flooding risk, as multiple
inches of rain fall over the same areas very hard hit from
Thursday. This very good overlap in the storm placement from
Thursday to Friday necessitated a risk upgrade across southern
Alabama for the Day 3/Friday period. Should this overlap continue
to hold and the widespread multiple inches of rain with localized
totals to double digits from Thursday occurs as forecast, it's
entirely feasible that the hardest hit areas may need further
upgrades to the flooding risk. Unfortunately the track record with
the CAMs ensembles on maintaining continuity day to day on where
the storms will occur is not very good, so any movement breaking
the overlap will greatly improve the rather ominous flooding
outlook for southern Alabama on Friday. Convective coverage over
Alabama should diminish greatly Friday night as heavier rains to
the west and the departing system to the east should put the state
in a relative ridging pattern, allowing for a much needed break
from the rainfall.

...Texas Hill Country...

Southeasterly flow of deep moisture from off the Gulf will
continue across much of Texas through the Day 3 period.
Northwestward moving convection on the leading edge of the deep
moisture will collide with storms that form along the dry line and
the Mexican mountains Friday evening, resulting in MCS development
that turns the storms back towards the best instability to the
southeast. This should result in some areas seeing multiple rounds
of heavy rain producing storms over the historically flash flood
prone region of the Texas Hill Country. Thus, a Slight Risk area
remains in effect for the region. Lesser amounts of rain are
expected further east into north-central Texas and the Metroplex,
so the Slight Risk inherited with downgraded in that area.

Wegman
=20

Day 4 and Day 5
Valid 12Z Sat Jun 20 2026 - 12Z Mon Jun 22 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE OF CENTRAL PLAINS THROUGH THE MID MISSISSIPPI INTO THE LOWER
OHIO VALLEY...

...2030Z Update...

The daytime runs of the deterministic models and the ensemble
guidance continued to focus on the Central Plains on Day 4 and
in/near the Mid-Mississippi Valley on Day 5 as having the highest
probability for excessive rainfall. Even though there were some run
to run adjustments...the placement of the outlook areas were consistent
and well covered by the on-going outlook. Few changes were made
this cycle.

Bann

Day 4...

A well-defined 500mb shortwave trough will move from the Great
Basin into the northern Rockies midday Saturday, reaching the
northern High Plains by Saturday night. Ahead of a southward
advancing Canadian cold front, a northward-lifting warm front
across the central Plains will lead an anomalous moisture plume
into an increasing unstable environment. While exact convective
placement varies, the deterministic models remain in generally
good agreement -- depicting a deepening surface low over the
central Plains that will help to focus moisture along the leading
edge of a strengthening low level jet. A deepening pool of
moisture (PWs increasing to 1.5-2 inches) over central
Nebraska/Kansas eastward into southwestern Iowa and western to
central Missouri will support efficient rainfall rates. This ample
moisture along with large- scale ascent afforded by mid-level
shortwave and right- entrance region jet forcing will further
encourage heavy rainfall and the potential for flash flooding
across the region. Therefore, a Slight Risk was maintained across
the region. Farther south, a weakening frontal boundary and
residual tropical moisture will trigger additional thunderstorms
from South Texas across the Gulf Coast. Localized flooding will
likely remain a threat given the increasing sensitive soils.

Day 5...=20

Forecast confidence lowers notably heading into the
latter half of the weekend as guidance begins to diverge on the
track of the leading wave forming over the central Plains on Day 4.
Notably, the ECMWF offers one of the more northerly solutions
compared to other guidance. Beyond the primary wave's track from
the Midwest into the East, considerable model spread exists
regarding the timing of the trailing front and subsequent wave and
storm development. With the continuation of ample moisture,
instability, and strong forcing areas of heavy rainfall and flash
flooding appear likely. Given the model spread, the outlook area,
including a Slight Risk extending from the lower Missouri to the
lower Ohio Valley, relied most heavily on a multi-model ensemble
mean.

Pereira
=20

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!7wcIAar4-cV5emFCBRjOyv7KCofT-6Ti99YfH5Ts9ZCA= XqdmgCzEFmYBJSQmtKIbGmkyxk3lDWEhIoqW37zFsFkB1cE$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!7wcIAar4-cV5emFCBRjOyv7KCofT-6Ti99YfH5Ts9ZCA= XqdmgCzEFmYBJSQmtKIbGmkyxk3lDWEhIoqW37zFaYPMfe4$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!7wcIAar4-cV5emFCBRjOyv7KCofT-6Ti99YfH5Ts9ZCA= XqdmgCzEFmYBJSQmtKIbGmkyxk3lDWEhIoqW37zFEqI5vi4$=20



$$

=3D =3D =3D
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FOUS30 KWBC 180057
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
857 PM EDT Wed Jun 17 2026

Day 1
Valid 01Z Thu Jun 18 2026 - 12Z Thu Jun 18 2026

...THERE ARE MODERATE RISKS FOR EXCESSIVE RAINFALL FOR PORTIONS OF ILLINOIS/INDIANA AS WELL AS THE MISSISSIPPI DELTA...

01Z Excessive Rainfall Discussion Update...
Heavy to excessive rainfall still expected during the overnight
hours along the Gulf coast as moisture transport continues from the
Gulf and interacts with a variety of forcings including an MCV
associated with a circulation east of Arthur. A quick look at
soundings showed CAPE values in the 2000 to 3000 J per kg range
with precipitable water values running 2.3 to 2.6 inches. The
resulting rainfall rates of 1 to 1.5 inches per hour per the KHDC
88D. Suspect the HRRR runs from late afternoon were a bit too far
to the west based on latest radar and satellite imagery so
maintained the Moderate risk area without change given the other
guidance. Mesoscale Precipitation Discussion 0439 was valid until
18/0600Z.

The Moderate Risk area over portions of Midwest/Upper Midwest and
Great Lakes region and surrounding Slight/Marginal risk areas were
removed in the wake of an advancing cold front given the amount of
dry air being advected into the region. With convection remaining
active from eastern Kansas and southwest Missouri into the Ohio
Valley...the risk of excessive rainfall persists into the overnight
hours. There was some moderate rainfall associated with a channeled
mid-level jet from Minnesota into Wisconsin/extreme northern
Illinois with flooding concern. The concern arises from the soils
being primed by rainfall in the past couple of days and not so much
by blockbuster rainfall rates.

Southwest United States...
Given low level moisture being capped by broad but fairly weak
subsidence associated with an upper high...the expectation is for
any on-going convection over Arizona or New Mexico should weaken
and dissipate quickly with the loss of daytime heating.

Bann
...1600 UTC Update...
The Moderate Risk in the Midwest has been shifted south based on
current observational trends and the latest 12Z hi-res guidance
with regards to an ongoing MCS over northern Illinois. This will
likely limit the northward progression of the warm front/effective
outflow into the afternoon hours bringing the greatest threat for
heavy rainfall/flash flooding along a west-northwest to east-
southeast axis through central Illinois into central Indiana. This
includes both the more intense storms on the southern/southwest end
of the ongoing MCS able to tap into greater moisture/instability
along the warm front as well as for additional storm development
that will focus along the warm front/effective outflow. Repeated development/potential training of robust, heavy rainfall producing
storms (rainfall rates ~ 2 inches/hour) leading to totals of 3-5",
locally as high as 6-7", will pose a threat for scattered to
widespread incidents of flash flooding.
Further south, the Moderate/Slight Risk areas have also been
minimally adjusted based on the latest 12Z guidance along and east
of the track of what is now Tropical Storm Arthur. Plentiful
tropical moisture will support additional rainfall totals of 3-5"
with localized amounts as high as 6-10". The highest totals look to
focus along a corridor within southeastern Louisiana generally
between Baton Rouge and New Orleans where the greatest threat for
more widespread instances of flash flooding will exist.
Putnam
...Previous Discussion...
...Chicagoland...
A potent low racing out of the Plains and across the Great Lakes
today will run into an increasingly moist air mass in place ahead
of the low over the Midwest. As the low approaches the Chicagoland
region late morning, convection will break out along the low's warm
front extending east of the low center. The initial hit of rain
with the warm front is unlikely to feature too much heavy rain,
though embedded elevated convection could make for brief heavier
downpours. Immediately behind the warm front, however, a surge of
moisture and instability will fuel backbuilding thunderstorms
during the afternoon ahead of a strong cold front trailing behind
the low. These storms are progged by many of the CAMs to generate
into several broken lines of storms as they cross northern Illinois
and into northern Indiana and southern Michigan through the late afternoon/early evening. These storms will have ample forcing
allowing them to organize into severe clusters of storms. They are
likely to produce locally heavy rainfall rates of up to 2 inches
per hour where they backbuild. However, since the series of line
segments will be sufficiently separated by much lighter or no rain,
it seems any flash flooding that results from these storms will be
more localized and less widespread. Further, as mentioned, the
storms will be racing very quickly, likely moving at 40+ mph. This
will greatly reduce the time any one area sees heavy rain, but
since the lines are expected to align parallel to the windflow,
those areas may see a bit longer time of heavy rainfall.
Hydrologically, the Chicagoland area has seen several bouts of
heavy rain in recent weeks that have left the soils above normal
for moisture content as well as prone to flash flooding with
sufficiently heavy rain. Of course, the large urban area of Chicago
will also help to worsen any flash flooding that develops, so in
those local areas where heavy rain overlaps with urban areas,
locally considerable flash flooding is possible. Further east into
Indiana, eastern Michigan, and eventually northwestern Ohio, the
lines of storms this evening should align with the cold front and
largely orthogonal to the flow. This should lower the flash
flooding risk in these areas, despite similarly favorable
hydrology.
...Mississippi Delta...
The moisture plume of Potential Tropical Cyclone 1 (PTC1) will
continue to slowly advect northeast across the northwestern Gulf
and into southern Louisiana today into tonight. For much of the
day, the heaviest rains will remain offshore, and except for
occasional showers and an isolated storm or 2, much of the area
should not contend with much heavy rain. That changes tonight as
the center of circulation of what may be Tropical Storm Arthur
moves ashore near the TX/LA border. All of the deep moisture will
be east of the center of circulation, so that will direct the
fire-hose of heavy rain into south-central Louisiana, from the
Abbeville/New Iberia area northeast near Baton Rouge and into
southern Mississippi after midnight. By that point, the diurnal
strengthening of the nocturnal jet will function as the the primary
driver of heavy rain as northeastward moving storms backbuild into
the jet. The area from around Baton Rouge northeast to the north of
Lake Pontchartrain and into far southern Mississippi is likely to
be the corridor with the heaviest rain.
There is considerable uncertainty first of the eastern extent of
the axis of heaviest rain, particularly in relation to the New
Orleans Metro. For now most of the guidance makes a very tight
gradient of moisture, which most of the city remains on the drier
side of. However, this axis of heaviest rain has been shifting
east from model run to model run over the last couple days, which
any further eastward drift would bring New Orleans right into the
corridor of multiple-inch per hour rainfall for multiple hours.
Regardless, even if New Orleans misses out on the heaviest
rainfall, feeder bands of showers and storms could still cause
localized flash flooding in the city. Thus, the Moderate Risk
remains largely unchanged and includes New Orleans. More than a
couple CAMs do bring strong cells over the city, which would very
quickly lead to flooding problems.
Wegman
=20

Day 2
Valid 12Z Thu Jun 18 2026 - 12Z Fri Jun 19 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE SOUTHEAST...

...2030 UTC Update...

Only a few minor areal adjustments were made to the inherited risk
areas with the prior forecast reasoning remaining on track for the
Southeast, Ohio/Tennessee Valleys, and areas further west into Arkansas/Oklahoma. The most notable was to expand the Moderate Risk
back northeast a bit to include metro Atlanta. While rain totals
in the hi-res guidance tend to be lower overall further north than
the noted shift south overnight, the expected track of the
remnants of what is now Tropical Storm Arthur will pass very close
to the region. This will bring intense low-level flow (50 kts+) and
high PWATs (2-3") northward which could lead to some more intense
rainfall and heavier totals than currently depicted in the
guidance, and at least some of the hi-res runs showed the potential
for totals of 3-4". The urban area will also remain more sensitive
compared to elsewhere even if totals do not match some of the
higher end amounts anticipated further south. Otherwise, the rest
of the region was left mostly untouched. The latest 12Z hi-res
guidance depicted the potential for significant rainfall totals
particularly across southern portions of the Moderate Risk area
(southern Alabama into the western FLorida Panhandle), with areal
average totals in the 4-5" range and locally higher totals as much
as 6-10", more than sufficient for scattered to widespread flash
flooding. The HREF and RRFS both showed moderate probabilities
(40-60%) for totals of greater than 8 inches. One other adjustment
was to extend the Marginal Risk further westward across the
southern Plains into portions of the Texas Panhandle and eastern
New Mexico where afternoon/evening storms ahead of a sagging cold
front could bring a couple heavier downpours and possibly some
isolated flooding concerns within cities.

Putnam

...Previous Discussion...

...Southeast...

Very heavy rain associated with what will be the remnants of PTC1
will be ongoing at the start of the period over most of southern
Mississippi and likely extending into southwestern Alabama. These
storms will be fueled by a strong low level jet pumping deep
tropical moisture into a corridor that covers much of the Moderate
Risk area. By around midday, the rapidly increasing instability and
the typical weakening of the low level jet will allow the
widespread convection to transition into training lines of storms
that track east with time, as the line gradually drifts south
towards the greatest instability and moisture source that is the
Gulf. Thus, the greatest focus of heaviest rain now appears to set
up from southeastern Mississippi east across the southern tier of
Alabama and far western Georgia. 3+ inch/hour rainfall rates from
individual storms will combine with multiple hours of rain as the
storms train along the east-west oriented lines. Storm total
rainfall for the day could easily exceed 8 inches in spots. Mobile,
AL will be the biggest city in the crosshairs of the heaviest
rainfall.

With this rather dramatic southward shift in the guidance of where
the heaviest rainfall totals are expected, the Moderate Risk
inherited was trimmed significantly on the north side, while
expanded across southeast Alabama, the western Florida Panhandle,
and far southwestern Georgia. The Moderate Risk was downgraded out
of both the Birmingham and Atlanta metros as those areas see
leftover heavy rains from the much more potent and heavy rain
producing storms much closer to the Gulf Coast. Nonetheless,
periodic convection and a long duration of light to moderate rain
is still expected over those metros, so the higher-end Slight
remains in effect. Convective coverage greatly decreases Thursday
night over all of the Southeast, but isolated to widely scattered
storms could persist through the night in some areas.

...Ohio/Tennessee Valleys...

Further north from the Gulf Coast along the Ohio and Tennessee
Valleys, a cold front will start the day following roughly parallel
to the Ohio River. The front will slowly sink southward over
Kentucky through the day. Meanwhile, daytime heating and
unidirectional southwesterly flow ahead of the front is expected to
generate a long line of storms. The storms will be training and
backbuilding along the KY/TN border and extending into West
Virginia. Guidance has shifted a bit further south, especially with
the western end of the line, so the higher-end Slight now follows
the entire length of the KY/TN border, and now includes Nashville,
while the Ohio River has largely been removed from the risk area.
With nightfall and the loss of daytime heating, the flash flooding
risk from storms will also diminish.

...Arkansas/Oklahoma...

On Thursday night, the westernmost extension of the low-level jet
over Texas will run into the same stalled out front that extends
east into Kentucky. This clash of air masses is likely to result in
the development of an MCS over eastern Oklahoma, which will then
propagate southeastward into western Arkansas. Here too the soils
are wetter than normal from multiple bouts of heavy rain in recent
weeks, so a Slight Risk remains in place over the area with few
changes.

Wegman
=20

Day 3
Valid 12Z Fri Jun 19 2026 - 12Z Sat Jun 20 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR MUCH OF
SOUTHERN ALABAMA...

...2030 UTC Update...

Only very minimal areal changes were made to the inherited risk
areas as the prior forecast is consistent with the latest 00/12Z
guidance for both the Southeast as well as central/western Texas.
Rainfall totals across the Moderate/Slight Risk areas in the
Southeast will likely be down overall compared to Thursday as the
remnants of what is now Tropical Storm Arthur depart the region.
However, the region will remain much more susceptible to
additional rainfall given the amounts expected Thursday,
particularly for those in the Moderate Risk area across southern
Alabama into the Florida Panhandle which overlaps Thursday's risk
area. It likely will not take much to lead to additional flash
flooding as well as exacerbate any ongoing flooding.

Putnam

...Previous Discussion...
...Southeast...
Any lull in heavy rainfall across southern Alabama from Thursday
night behind the precipitation shield associated with the remnants
of Potential Tropical Cyclone 1 will end in a hurry Friday morning
as the cold front over the Tennessee Valley continues to press
southward and runs into the ongoing southerly flow and low-level
jet of deep tropical moisture from off the Gulf. The clash of these
air masses looks to maximize over southern Alabama, where storms
are likely to continue in some form or fashion for much of the day
Friday. Assuming the multiple inches of rain from Thursday occurs
in these same areas, the slightly lower storm total rain on Friday
will make little difference for the flooding risk, as multiple
inches of rain fall over the same areas very hard hit from
Thursday. This very good overlap in the storm placement from
Thursday to Friday necessitated a risk upgrade across southern
Alabama for the Day 3/Friday period. Should this overlap continue
to hold and the widespread multiple inches of rain with localized
totals to double digits from Thursday occurs as forecast, it's
entirely feasible that the hardest hit areas may need further
upgrades to the flooding risk. Unfortunately the track record with
the CAMs ensembles on maintaining continuity day to day on where
the storms will occur is not very good, so any movement breaking
the overlap will greatly improve the rather ominous flooding
outlook for southern Alabama on Friday. Convective coverage over
Alabama should diminish greatly Friday night as heavier rains to
the west and the departing system to the east should put the state
in a relative ridging pattern, allowing for a much needed break
from the rainfall.
...Texas Hill Country...
Southeasterly flow of deep moisture from off the Gulf will
continue across much of Texas through the Day 3 period.
Northwestward moving convection on the leading edge of the deep
moisture will collide with storms that form along the dry line and
the Mexican mountains Friday evening, resulting in MCS development
that turns the storms back towards the best instability to the
southeast. This should result in some areas seeing multiple rounds
of heavy rain producing storms over the historically flash flood
prone region of the Texas Hill Country. Thus, a Slight Risk area
remains in effect for the region. Lesser amounts of rain are
expected further east into north-central Texas and the Metroplex,
so the Slight Risk inherited with downgraded in that area.
Wegman
=20

Day 4 and Day 5

Valid 12Z Sat Jun 20 2026 - 12Z Mon Jun 22 2026
...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE OF CENTRAL PLAINS THROUGH THE MID MISSISSIPPI INTO THE LOWER
OHIO VALLEY...
2030Z Update...
The daytime runs of the deterministic models and the ensemble
guidance continued to focus on the Central Plains on Day 4 and
in/near the Mid-Mississippi Valley on Day 5 as having the highest
probability for excessive rainfall. Even though there were some run
to run adjustments...the placement of the outlook areas were consistent
and well covered by the on-going outlook. Few changes were made
this cycle.
Bann
Day 4...
A well-defined 500mb shortwave trough will move from the Great
Basin into the northern Rockies midday Saturday, reaching the
northern High Plains by Saturday night. Ahead of a southward
advancing Canadian cold front, a northward-lifting warm front
across the central Plains will lead an anomalous moisture plume
into an increasing unstable environment. While exact convective
placement varies, the deterministic models remain in generally
good agreement -- depicting a deepening surface low over the
central Plains that will help to focus moisture along the leading
edge of a strengthening low level jet. A deepening pool of
moisture (PWs increasing to 1.5-2 inches) over central
Nebraska/Kansas eastward into southwestern Iowa and western to
central Missouri will support efficient rainfall rates. This ample
moisture along with large- scale ascent afforded by mid-level
shortwave and right- entrance region jet forcing will further
encourage heavy rainfall and the potential for flash flooding
across the region. Therefore, a Slight Risk was maintained across
the region. Farther south, a weakening frontal boundary and
residual tropical moisture will trigger additional thunderstorms
from South Texas across the Gulf Coast. Localized flooding will
likely remain a threat given the increasing sensitive soils.
Day 5... Forecast confidence lowers notably heading into the
latter half of the weekend as guidance begins to diverge on the
track of the leading wave forming over the central Plains on Day 4.
Notably, the ECMWF offers one of the more northerly solutions
compared to other guidance. Beyond the primary wave's track from
the Midwest into the East, considerable model spread exists
regarding the timing of the trailing front and subsequent wave and
storm development. With the continuation of ample moisture,
instability, and strong forcing areas of heavy rainfall and flash
flooding appear likely. Given the model spread, the outlook area,
including a Slight Risk extending from the lower Missouri to the
lower Ohio Valley, relied most heavily on a multi-model ensemble
mean.
Pereira
=20

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!6e-8VcJNAvzMawidZ7zXGIxgsCOTJeXMSzIBUtOsPy9v= UF7XjjdrGjXP9ebEwCYTQ_uhmlEckxKk_CD_40z65t-TJBw$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!6e-8VcJNAvzMawidZ7zXGIxgsCOTJeXMSzIBUtOsPy9v= UF7XjjdrGjXP9ebEwCYTQ_uhmlEckxKk_CD_40z6ho_QzaU$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!6e-8VcJNAvzMawidZ7zXGIxgsCOTJeXMSzIBUtOsPy9v= UF7XjjdrGjXP9ebEwCYTQ_uhmlEckxKk_CD_40z6sPgcb2U$=20



$$

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FOUS30 KWBC 180826
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
426 AM EDT Thu Jun 18 2026

Day 1
Valid 12Z Thu Jun 18 2026 - 12Z Fri Jun 19 2026

...THERE IS A HIGH RISK OF EXCESSIVE RAINFALL FOR THE CENTRAL GULF
COAST...

...WIDESPREAD AND POTENTIALLY LIFE THREATENING FLASH FLOODING
LIKELY TODAY FOR THE CENTRAL GULF COAST...

...Southeast...

The remnants of Post Tropical Cyclone Arthur are moving into the
Central Gulf Coast this morning. While the cyclone center may have
dissipated, the moisture plume and associated rainfall shield most
certainly have not. Rainfall moving into southeastern Louisiana
right now are producing rates to 3 inches per hour. These kinds of
rainfall rates are expected to continue with the strongest cells
for much of the day today across the central Gulf Coast. An
impressive 50 kt low level jet at 850 is advecting very deep
tropical moisture into the coast. This is pushing PWATs to over 2.6
inches. Meanwhile instability over the Gulf is up to 4,000 J/kg.
This is supporting very efficient cells capable of multiple inch
per hour rates to the east of the remnant circulation center.
Multiple waves of storms will track south to north across eastern
Louisiana into southern Mississippi this morning. The area has been
hard hit with heavy rain in recent days, so larger rivers are
already flooding, and soils are nearly saturated, so nearly all of
the heavy rainfall is expected to convert to runoff, resulting in
more significant river, stream, and creek rises though the morning.

The eastern side of the plume of moisture will spawn additional
numerous thunderstorms into southern Alabama and the Florida
Panhandle through midday. The storm organization is expected to
change a bit into the afternoon with peak heating. To the west
across Mississippi and Louisiana, backbuilding and training
convection is expected to form into 1 or 2 nearly stationary lines,
as the individual cells embedded within train towards the east
along the line. Meanwhile, over Alabama, multiple lines of eastward
moving lines of storms will get the flooding and heavy rainfall
started as early as mid-morning. The western end of the line in
LA/MS will become the trailing storms on the southwest end of the
MCS associated with post tropical cyclone Arthur. This line will
very slowly drift southeastward towards the Gulf Coast, likely
impacting Mobile and eventually the Pensacola area, as well as
points north. This will result in multiple hours from mid-afternoon
into the evening where training storms track over the same areas.
The eastward moving convection is expected to move faster towards
the east than the storms can backbuild, so the trailing line
responsible for the worst flooding should gradually shift east as
well. The storms could persist as long as until midnight in the
Florida Panhandle, but most guidance has it moving on and
dissipating earlier in the evening. Regardless, with potential for
multiple inch per hour rainfall rates with numerous storms through
the day tracking over the same areas, the storm total rainfall in
these areas is likely to pile up very quickly. Guidance suggests
rainfall totals in many areas of the High Risk could exceed 12
inches, though local amounts could approach 20 inches.

Widespread and potentially life threatening flash flooding is
likely as a result of these double-digit rainfall numbers. Urban
areas that could be impacted from New Orleans (in a higher-end
Moderate Risk), Mobile, and Pensacola could see life-threatening
flash flooding occur as a result. Everyone should heed the advice
of local authorities as warnings are issued.

Across central Alabama into northern Georgia, storm coverage and
intensity of the strongest cells are expected to be a bit lower,
but antecedent soil conditions remain nearly saturated. Multiple
hours of moderate to at times heavy rain are expected up as far
north as Birmingham and northeast as Atlanta. The Moderate Risk for
these areas remains in place with few changes. An eastward
expansion of the Moderate Risk in west-central Georgia was also
made.

...Ohio/Tennessee Valleys...

A cold front pushing south across the Ohio Valley today will run
into the northern extent of the deep plume of tropical moisture
associated with the remnants of Arthur. With daytime heating, the
clashing of air masses along the front will result in numerous
showers and thunderstorms developing along the front, which will
likely be along the KY/TN border, extending ENE into eastern
Kentucky and southern West Virginia. The storms will be in a
favorable environment for training as the plume of moisture tracks
parallel to the front as well. A shortwave trough will help the
front advance south and east across the area more quickly this
evening through tonight, which should end any backbuilding and
training from the afternoon and allow everything to progress
eastward, ending the flooding threat.

...Southwestern Oklahoma into North Texas...

Overnight tonight, an MCS is expected to develop across
southwestern Oklahoma and north Texas in response to both proximity
to the dry line, deep tropical moisture with PWATs approaching 2
inches, and a developing low over West Texas, encouraging the
formation of a low level jet into the storms. Given this is a
smaller feature than the remnants of Arthur to the east, the CAMs
are struggling much more with where and how long the storms in the
area will form, and where they will track. Most likely the storms
will remain along the Red River/OK-TX border. The inherited Slight
covering most of the rest of Oklahoma into Arkansas was dropped to
a Marginal as this MCS should remain well separated from the rains
with Arthur to the east, with little rain in between.

Wegman
=20

Day 2
Valid 12Z Fri Jun 19 2026 - 12Z Sat Jun 20 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR SOUTHERN
ALABAMA AND ADJACENT AREAS...

...Southeast...

While the plume of extreme moisture associated with the remnants of
Arthur will be exiting the Carolina coast at the start of the
period, deep tropical moisture will remain entrenched over much of
the Southeast on Friday. A cold front that tracked over the Ohio
Valley on Day 1/Thursday will continue edging southward into the
Southeast, bringing much drier air and relief to areas behind it.
Unfortunately ahead of it, the air mass will remain soupy. The
moisture off the Gulf will have turned eastward along the front on
Friday, which will do a couple things: 1) It will not prevent the
front from making more southward progress, as opposed to a
southerly low level jet which would actively work against a
southward moving front. 2) It will create a more unidirectional
wind flow through the depth of the atmosphere, which will support faster-moving, but training storms along the front. In addition to
any MCSs which could form in the soupy air mass early in the
morning, potentially multiple lines of storms will track
southeastward along the front into the area that just was hit with
Arthur's remnants the previous day. Thus, the Moderate Risk for
this area remains in effect. Expected rainfall for most areas will
generally stay between 1-3 inches on average, so the rainfall
amounts expected on Friday will pale in comparison to today.
However, given the expected flooding that will very much still be
ongoing on Friday, the addition of 1-3 inches of rain with locally
higher amounts where storm training persists longest over these
same areas still raised the flooding threat in the area to the
Moderate Risk category. Changes in where the heaviest rains
today/Day 1 occur may result in shifts of the Moderate Risk,
particularly if the heaviest expected rains occur further south and
west into Mississippi and eastern Louisiana. A few of the CAMs
models are hinting at that possibility.

...Southern Plains...

Across a large swath of Texas on Friday, multiple MCSs may impact
much of the state. On Friday morning, lingering MCSs from Oklahoma
and the Slight Risk on Day 1 may be ongoing into north-central
Texas Friday morning, including into the Metroplex. Widely
scattered instances of flash flooding will be possible with that.
More coverage of storms are expected Friday night. The typical
strengthening MCS will advect extreme instability and moisture over
all of the eastern half of the state. As storms form and organize
into MCSs, the potential for additional instances of flash flooding
will increase. There is considerable uncertainty as to where they
form and how they track, so a large swath of eastern Texas was
included in a Slight Risk, especially down towards San Antonio and
Houston, which have been impacted with heavy rains in recent days,
and soils remain wetter than normal.

Wegman

Day 3
Valid 12Z Sat Jun 20 2026 - 12Z Sun Jun 21 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
CENTRAL PLAINS AS WELL AS FOR PORTIONS OF THE SOUTHEAST...

...Central Plains...

A large area of heavy rain associated with a developing MCS
starting Saturday afternoon and continuing into Saturday night will
bring multiple inches of rain to a large area of southeastern
Nebraska through northwestern Missouri. Storms are expected to
initiate Saturday afternoon with peak heating. An LLJ of
southeasterly flow will pump deep Gulf moisture up the Plains
through the day. A developing surface low and upper level shortwave strengthening the low over Colorado will eject into the Plains.
This will force the dryline to race eastward in response. The warm
front associated with the low and the dry line will uplift the deep
moisture, resulting in widespread shower and thunderstorm
development in the form of an MCS. The MCS will track southeast
into southeastern Nebraska, far northern Kansas, and eventually to
the Missouri River. Additional storms capable of multiple inch per
hour rain rates will develop on the southern end of the MCS, where
the greatest rainfall totals will be. Urban areas in the path
including Lincoln and maybe Omaha, Nebraska, Topeka, Kansas, and
eventually St. Joseph and Kansas City, Missouri after midnight will
likely be impacted. Widely scattered instances of flash flooding
are likely. Given the amount of moisture present for these storms
to feed on and the urban areas likely to be impacted, additional
increases in forecast rainfall may require an upgrade to a Moderate
Risk with future updates. Since CAMs do poorly and the models
frequently shift where the heaviest rains will be leading up to an
event, the Moderate Risk was not considered at this time.

...Southeast...

An MCS tracking from the Ozarks following the same front that
entered interior portions of the Southeast as a cold front on
Friday will help that same front now retreat as a warm front on
Saturday. Heavy rains are expected Saturday morning over the Slight
Risk area from northern Mississippi to southern Alabama as storms
track southeastward along the retreating front. Daytime heating
will likely support additional clusters of storms into the
afternoon in these areas. The heaviest rains over the most
widespread area will be Saturday morning in northern Mississippi.
They will be less organized as they move into southern Alabama
Saturday afternoon, but given the prior day's expected rains in
these same areas, the Slight Risk includes southern Alabama as
well.

Wegman
=20

Day 4 and Day 5

Valid 12Z Sun Jun 21 2026 - 12Z Tue Jun 23 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM PORTIONS OF
THE OZARKS THROUGH THE MIDWEST AND INTO THE UPPER OHIO VALLEY...

Day 4... By the start of the day 4 forecast period a potent
shortwave and related surface low are expected to eject eastward
out of the central Plains into the Midwest. There will also be a
trailing frontal boundary extending into the southern Plains to add
a focus for additional thunderstorms. There remains some
uncertainty regarding the speed and latitude of these features, but
PWs above the 90th climatological percentile (per the 00z GEFS)
overlapping with soils likely still recovering from recent heavy
rain in the Midwest will lead to at least scattered flash flooding
concerns. NBM probabilities for at least 2" are between 30-55% and
cover much of the SLGT risk area. Locally higher totals are likely
given the convective environment. The progressive nature of these
storms may end up limiting the severity of flash flood impacts, but
a MDT risk upgrade is possible should training/back-building
elements become more obvious in the short range updates. This is
especially the case given the sensitivity of the affected regions
to additional rainfall.

Day 5... The shortwave and low pressure on day 4 is forecast to
continue east towards the Mid-Atlantic and Northeast, with
additional uncertainties in latitude and speed. Additionally,
thunderstorms should reform along the attached frontal boundary
extending westward across the Tennessee Valley and into the
southern Plains. At the moment most convection appears scattered in
nature and low confidence in placement of heavier QPF. Therefore, a
MRGL risk is highlighted and will be refined in future updates.
Additional thunderstorm activity is likely into the High Plains,
with uncertainty surrounding the impact of a nearby southern Canada
upper low on thunderstorm activity in the northern High Plains.

Snell
=20

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!6wFVMIUJw_BEgUAp9MEVaKlimOdhN82gWcvgwN3z4rs0= 83pn_wqQISE5KCNZ14Nw0-25eB2Wxfpemc2IjJK6DB6Lyew$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!6wFVMIUJw_BEgUAp9MEVaKlimOdhN82gWcvgwN3z4rs0= 83pn_wqQISE5KCNZ14Nw0-25eB2Wxfpemc2IjJK6RbON90o$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!6wFVMIUJw_BEgUAp9MEVaKlimOdhN82gWcvgwN3z4rs0= 83pn_wqQISE5KCNZ14Nw0-25eB2Wxfpemc2IjJK6x06I5-A$=20



$$

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FOUS30 KWBC 181559
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1159 AM EDT Thu Jun 18 2026

Day 1
Valid 16Z Thu Jun 18 2026 - 12Z Fri Jun 19 2026

...THERE IS A HIGH RISK OF EXCESSIVE RAINFALL FOR THE CENTRAL GULF
COAST...

...WIDESPREAD AND LIFE THREATENING FLASH FLOODING LIKELY TODAY FOR
THE CENTRAL GULF COAST...

...1600 UTC Update...

A widespread and life-threatening flash flood event is underway
across the central Gulf Coast and will continue to expand
northeastward deeper into the Southeast throughout the day. Flash
flood emergencies have already been issued both in southeastern and
central LA as well as southern Mississippi where bands of
backbuilding, training thunderstorms have already lead to MRMS
estimated rainfall totals of 9-11" (see WPC MPD #450 for more
details). Torrential rainfall is expected to continue throughout
the day with these ongoing storms as well as additional bands of
thunderstorms supported by a surface low associated with the
remnants of Tropical Storm Arthur, an impressive ~40-50 kt low
level jet off the Gulf, and daily-record level PWATS over 2". Some
modest adjustments were made to the inherited outlook based on
ongoing thunderstorms and the latest 12Z hi-res guidance including
a westward expansion of the High Risk to central Louisiana where
ongoing life-threatening flash flooding is occurring. A slight
northeastward expansion was also included across southern
Mississippi and Alabama given moderate to high probabilities from
the HREF of 5-8"+ of rainfall. Guidance in general has suggested a northeastward expansion of the flash flood risk bringing heightened
concern to southwestern to central Georgia as well as further
north into the southern Appalachians.

Elsewhere, the Slight Risk over portions of the southern
Plains/Texas was also expanded based on the latest 12Z hi-res
guidance. Thunderstorms are expected to develop later this evening
and into the overnight hours in vicinity of a wave of low pressure
along an approaching cold front and southward along the dryline.
Sporadic/slow storm motions and clustering of storms will support
locally heavy rainfall, especially if the collective
clustering/merging of cold pools can result in more organized
complexes as suggested by some of the hi-res guidance. This
includes both along the Red River Valley, where a Slight Risk is
already in place, as well as further south along the dryline into
the Texas Hill Country where the Slight Risk has been expanded.
Some of the latest hi-res guidance (including the RRFS) is more
bullish on the potential for heavier rainfall spreading southward
given expected storm motions and potential for a more organized
complex to develop.

Another round of thunderstorms is expected today over portions of
Arizona and New Mexico where some locally heavy rainfall/isolated
flash flooding will be possible given heightened moisture in place.
Most storms will likely be diurnally driven along the more complex
terrain. Increased moist southerly flow off the Atlantic into
interior New England/Upstate New York ahead of an approaching low
pressure system will also bring the threat for some locally heavy
rainfall (1-3" totals) and isolated flash flooding.

Putnam

...Previous Discussion...

...Southeast...

The remnants of Post Tropical Cyclone Arthur are moving into the
Central Gulf Coast this morning. While the cyclone center may have
dissipated, the moisture plume and associated rainfall shield most
certainly have not. Rainfall moving into southeastern Louisiana
right now are producing rates to 3 inches per hour. These kinds of
rainfall rates are expected to continue with the strongest cells
for much of the day today across the central Gulf Coast. An
impressive 50 kt low level jet at 850 is advecting very deep
tropical moisture into the coast. This is pushing PWATs to over 2.6
inches. Meanwhile instability over the Gulf is up to 4,000 J/kg.
This is supporting very efficient cells capable of multiple inch
per hour rates to the east of the remnant circulation center.
Multiple waves of storms will track south to north across eastern
Louisiana into southern Mississippi this morning. The area has been
hard hit with heavy rain in recent days, so larger rivers are
already flooding, and soils are nearly saturated, so nearly all of
the heavy rainfall is expected to convert to runoff, resulting in
more significant river, stream, and creek rises though the morning.

The eastern side of the plume of moisture will spawn additional
numerous thunderstorms into southern Alabama and the Florida
Panhandle through midday. The storm organization is expected to
change a bit into the afternoon with peak heating. To the west
across Mississippi and Louisiana, backbuilding and training
convection is expected to form into 1 or 2 nearly stationary lines,
as the individual cells embedded within train towards the east
along the line. Meanwhile, over Alabama, multiple lines of eastward
moving lines of storms will get the flooding and heavy rainfall
started as early as mid-morning. The western end of the line in
LA/MS will become the trailing storms on the southwest end of the
MCS associated with post tropical cyclone Arthur. This line will
very slowly drift southeastward towards the Gulf Coast, likely
impacting Mobile and eventually the Pensacola area, as well as
points north. This will result in multiple hours from mid-afternoon
into the evening where training storms track over the same areas.
The eastward moving convection is expected to move faster towards
the east than the storms can backbuild, so the trailing line
responsible for the worst flooding should gradually shift east as
well. The storms could persist as long as until midnight in the
Florida Panhandle, but most guidance has it moving on and
dissipating earlier in the evening. Regardless, with potential for
multiple inch per hour rainfall rates with numerous storms through
the day tracking over the same areas, the storm total rainfall in
these areas is likely to pile up very quickly. Guidance suggests
rainfall totals in many areas of the High Risk could exceed 12
inches, though local amounts could approach 20 inches.

Widespread and potentially life threatening flash flooding is
likely as a result of these double-digit rainfall numbers. Urban
areas that could be impacted from New Orleans (in a higher-end
Moderate Risk), Mobile, and Pensacola could see life-threatening
flash flooding occur as a result. Everyone should heed the advice
of local authorities as warnings are issued.

Across central Alabama into northern Georgia, storm coverage and
intensity of the strongest cells are expected to be a bit lower,
but antecedent soil conditions remain nearly saturated. Multiple
hours of moderate to at times heavy rain are expected up as far
north as Birmingham and northeast as Atlanta. The Moderate Risk for
these areas remains in place with few changes. An eastward
expansion of the Moderate Risk in west-central Georgia was also
made.

...Ohio/Tennessee Valleys...

A cold front pushing south across the Ohio Valley today will run
into the northern extent of the deep plume of tropical moisture
associated with the remnants of Arthur. With daytime heating, the
clashing of air masses along the front will result in numerous
showers and thunderstorms developing along the front, which will
likely be along the KY/TN border, extending ENE into eastern
Kentucky and southern West Virginia. The storms will be in a
favorable environment for training as the plume of moisture tracks
parallel to the front as well. A shortwave trough will help the
front advance south and east across the area more quickly this
evening through tonight, which should end any backbuilding and
training from the afternoon and allow everything to progress
eastward, ending the flooding threat.

...Southwestern Oklahoma into North Texas...

Overnight tonight, an MCS is expected to develop across
southwestern Oklahoma and north Texas in response to both proximity
to the dry line, deep tropical moisture with PWATs approaching 2
inches, and a developing low over West Texas, encouraging the
formation of a low level jet into the storms. Given this is a
smaller feature than the remnants of Arthur to the east, the CAMs
are struggling much more with where and how long the storms in the
area will form, and where they will track. Most likely the storms
will remain along the Red River/OK-TX border. The inherited Slight
covering most of the rest of Oklahoma into Arkansas was dropped to
a Marginal as this MCS should remain well separated from the rains
with Arthur to the east, with little rain in between.
Wegman
=20

Day 2
Valid 12Z Fri Jun 19 2026 - 12Z Sat Jun 20 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR SOUTHERN
ALABAMA AND ADJACENT AREAS...

...Southeast...

While the plume of extreme moisture associated with the remnants of
Arthur will be exiting the Carolina coast at the start of the
period, deep tropical moisture will remain entrenched over much of
the Southeast on Friday. A cold front that tracked over the Ohio
Valley on Day 1/Thursday will continue edging southward into the
Southeast, bringing much drier air and relief to areas behind it.
Unfortunately ahead of it, the air mass will remain soupy. The
moisture off the Gulf will have turned eastward along the front on
Friday, which will do a couple things: 1) It will not prevent the
front from making more southward progress, as opposed to a
southerly low level jet which would actively work against a
southward moving front. 2) It will create a more unidirectional
wind flow through the depth of the atmosphere, which will support faster-moving, but training storms along the front. In addition to
any MCSs which could form in the soupy air mass early in the
morning, potentially multiple lines of storms will track
southeastward along the front into the area that just was hit with
Arthur's remnants the previous day. Thus, the Moderate Risk for
this area remains in effect. Expected rainfall for most areas will
generally stay between 1-3 inches on average, so the rainfall
amounts expected on Friday will pale in comparison to today.
However, given the expected flooding that will very much still be
ongoing on Friday, the addition of 1-3 inches of rain with locally
higher amounts where storm training persists longest over these
same areas still raised the flooding threat in the area to the
Moderate Risk category. Changes in where the heaviest rains
today/Day 1 occur may result in shifts of the Moderate Risk,
particularly if the heaviest expected rains occur further south and
west into Mississippi and eastern Louisiana. A few of the CAMs
models are hinting at that possibility.

...Southern Plains...

Across a large swath of Texas on Friday, multiple MCSs may impact
much of the state. On Friday morning, lingering MCSs from Oklahoma
and the Slight Risk on Day 1 may be ongoing into north-central
Texas Friday morning, including into the Metroplex. Widely
scattered instances of flash flooding will be possible with that.
More coverage of storms are expected Friday night. The typical
strengthening MCS will advect extreme instability and moisture over
all of the eastern half of the state. As storms form and organize
into MCSs, the potential for additional instances of flash flooding
will increase. There is considerable uncertainty as to where they
form and how they track, so a large swath of eastern Texas was
included in a Slight Risk, especially down towards San Antonio and
Houston, which have been impacted with heavy rains in recent days,
and soils remain wetter than normal.
=20

Day 3
Valid 12Z Sat Jun 20 2026 - 12Z Sun Jun 21 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF THE
CENTRAL PLAINS AS WELL AS FOR PORTIONS OF THE SOUTHEAST...

...Central Plains...

A large area of heavy rain associated with a developing MCS
starting Saturday afternoon and continuing into Saturday night will
bring multiple inches of rain to a large area of southeastern
Nebraska through northwestern Missouri. Storms are expected to
initiate Saturday afternoon with peak heating. An LLJ of
southeasterly flow will pump deep Gulf moisture up the Plains
through the day. A developing surface low and upper level shortwave strengthening the low over Colorado will eject into the Plains.
This will force the dryline to race eastward in response. The warm
front associated with the low and the dry line will uplift the deep
moisture, resulting in widespread shower and thunderstorm
development in the form of an MCS. The MCS will track southeast
into southeastern Nebraska, far northern Kansas, and eventually to
the Missouri River. Additional storms capable of multiple inch per
hour rain rates will develop on the southern end of the MCS, where
the greatest rainfall totals will be. Urban areas in the path
including Lincoln and maybe Omaha, Nebraska, Topeka, Kansas, and
eventually St. Joseph and Kansas City, Missouri after midnight will
likely be impacted. Widely scattered instances of flash flooding
are likely. Given the amount of moisture present for these storms
to feed on and the urban areas likely to be impacted, additional
increases in forecast rainfall may require an upgrade to a Moderate
Risk with future updates. Since CAMs do poorly and the models
frequently shift where the heaviest rains will be leading up to an
event, the Moderate Risk was not considered at this time.

...Southeast...

An MCS tracking from the Ozarks following the same front that
entered interior portions of the Southeast as a cold front on
Friday will help that same front now retreat as a warm front on
Saturday. Heavy rains are expected Saturday morning over the Slight
Risk area from northern Mississippi to southern Alabama as storms
track southeastward along the retreating front. Daytime heating
will likely support additional clusters of storms into the
afternoon in these areas. The heaviest rains over the most
widespread area will be Saturday morning in northern Mississippi.
They will be less organized as they move into southern Alabama
Saturday afternoon, but given the prior day's expected rains in
these same areas, the Slight Risk includes southern Alabama as
well.

Wegman
=20

Day 4 and Day 5

Valid 12Z Sun Jun 21 2026 - 12Z Tue Jun 23 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM PORTIONS OF
THE OZARKS THROUGH THE MIDWEST AND INTO THE UPPER OHIO VALLEY...

Day 4... By the start of the day 4 forecast period a potent
shortwave and related surface low are expected to eject eastward
out of the central Plains into the Midwest. There will also be a
trailing frontal boundary extending into the southern Plains to add
a focus for additional thunderstorms. There remains some
uncertainty regarding the speed and latitude of these features, but
PWs above the 90th climatological percentile (per the 00z GEFS)
overlapping with soils likely still recovering from recent heavy
rain in the Midwest will lead to at least scattered flash flooding
concerns. NBM probabilities for at least 2" are between 30-55% and
cover much of the SLGT risk area. Locally higher totals are likely
given the convective environment. The progressive nature of these
storms may end up limiting the severity of flash flood impacts, but
a MDT risk upgrade is possible should training/back-building
elements become more obvious in the short range updates. This is
especially the case given the sensitivity of the affected regions
to additional rainfall.

Day 5... The shortwave and low pressure on day 4 is forecast to
continue east towards the Mid-Atlantic and Northeast, with
additional uncertainties in latitude and speed. Additionally,
thunderstorms should reform along the attached frontal boundary
extending westward across the Tennessee Valley and into the
southern Plains. At the moment most convection appears scattered in
nature and low confidence in placement of heavier QPF. Therefore, a
MRGL risk is highlighted and will be refined in future updates.
Additional thunderstorm activity is likely into the High Plains,
with uncertainty surrounding the impact of a nearby southern Canada
upper low on thunderstorm activity in the northern High Plains.
Snell
=20

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!-rPwswWCf8MZfL6GC3Qtmb3TMuDJB6yf7uKd-C-hyHcH= axLhpd8ucoYh7gzWkni8H0dQZRhPoKWKoAOc-S_2JeVuyWc$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!-rPwswWCf8MZfL6GC3Qtmb3TMuDJB6yf7uKd-C-hyHcH= axLhpd8ucoYh7gzWkni8H0dQZRhPoKWKoAOc-S_28oafYKY$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!-rPwswWCf8MZfL6GC3Qtmb3TMuDJB6yf7uKd-C-hyHcH= axLhpd8ucoYh7gzWkni8H0dQZRhPoKWKoAOc-S_2kxcuimI$=20



$$

=3D =3D =3D
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FOUS30 KWBC 182030
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
430 PM EDT Thu Jun 18 2026

Day 1
Valid 16Z Thu Jun 18 2026 - 12Z Fri Jun 19 2026

...THERE IS A HIGH RISK OF EXCESSIVE RAINFALL FOR THE CENTRAL GULF
COAST...

...WIDESPREAD AND LIFE THREATENING FLASH FLOODING LIKELY TODAY FOR
THE CENTRAL GULF COAST...

...1600 UTC Update...

A widespread and life-threatening flash flood event is underway
across the central Gulf Coast and will continue to expand
northeastward deeper into the Southeast throughout the day. Flash
flood emergencies have already been issued both in southeastern and
central LA as well as southern Mississippi where bands of
backbuilding, training thunderstorms have already lead to MRMS
estimated rainfall totals of 9-11" (see WPC MPD #450 for more
details). Torrential rainfall is expected to continue throughout
the day with these ongoing storms as well as additional bands of
thunderstorms supported by a surface low associated with the
remnants of Tropical Storm Arthur, an impressive ~40-50 kt low
level jet off the Gulf, and daily-record level PWATS over 2". Some
modest adjustments were made to the inherited outlook based on
ongoing thunderstorms and the latest 12Z hi-res guidance including
a westward expansion of the High Risk to central Louisiana where
ongoing life-threatening flash flooding is occurring. A slight
northeastward expansion was also included across southern
Mississippi and Alabama given moderate to high probabilities from
the HREF of 5-8"+ of rainfall. Guidance in general has suggested a northeastward expansion of the flash flood risk bringing heightened
concern to southwestern to central Georgia as well as further
north into the southern Appalachians.

Elsewhere, the Slight Risk over portions of the southern
Plains/Texas was also expanded based on the latest 12Z hi-res
guidance. Thunderstorms are expected to develop later this evening
and into the overnight hours in vicinity of a wave of low pressure
along an approaching cold front and southward along the dryline.
Sporadic/slow storm motions and clustering of storms will support
locally heavy rainfall, especially if the collective
clustering/merging of cold pools can result in more organized
complexes as suggested by some of the hi-res guidance. This
includes both along the Red River Valley, where a Slight Risk is
already in place, as well as further south along the dryline into
the Texas Hill Country where the Slight Risk has been expanded.
Some of the latest hi-res guidance (including the RRFS) is more
bullish on the potential for heavier rainfall spreading southward
given expected storm motions and potential for a more organized
complex to develop.

Another round of thunderstorms is expected today over portions of
Arizona and New Mexico where some locally heavy rainfall/isolated
flash flooding will be possible given heightened moisture in place.
Most storms will likely be diurnally driven along the more complex
terrain. Increased moist southerly flow off the Atlantic into
interior New England/Upstate New York ahead of an approaching low
pressure system will also bring the threat for some locally heavy
rainfall (1-3" totals) and isolated flash flooding.

Putnam

...Previous Discussion...

...Southeast...

The remnants of Post Tropical Cyclone Arthur are moving into the
Central Gulf Coast this morning. While the cyclone center may have
dissipated, the moisture plume and associated rainfall shield most
certainly have not. Rainfall moving into southeastern Louisiana
right now are producing rates to 3 inches per hour. These kinds of
rainfall rates are expected to continue with the strongest cells
for much of the day today across the central Gulf Coast. An
impressive 50 kt low level jet at 850 is advecting very deep
tropical moisture into the coast. This is pushing PWATs to over 2.6
inches. Meanwhile instability over the Gulf is up to 4,000 J/kg.
This is supporting very efficient cells capable of multiple inch
per hour rates to the east of the remnant circulation center.
Multiple waves of storms will track south to north across eastern
Louisiana into southern Mississippi this morning. The area has been
hard hit with heavy rain in recent days, so larger rivers are
already flooding, and soils are nearly saturated, so nearly all of
the heavy rainfall is expected to convert to runoff, resulting in
more significant river, stream, and creek rises though the morning.
The eastern side of the plume of moisture will spawn additional
numerous thunderstorms into southern Alabama and the Florida
Panhandle through midday. The storm organization is expected to
change a bit into the afternoon with peak heating. To the west
across Mississippi and Louisiana, backbuilding and training
convection is expected to form into 1 or 2 nearly stationary lines,
as the individual cells embedded within train towards the east
along the line. Meanwhile, over Alabama, multiple lines of eastward
moving lines of storms will get the flooding and heavy rainfall
started as early as mid-morning. The western end of the line in
LA/MS will become the trailing storms on the southwest end of the
MCS associated with post tropical cyclone Arthur. This line will
very slowly drift southeastward towards the Gulf Coast, likely
impacting Mobile and eventually the Pensacola area, as well as
points north. This will result in multiple hours from mid-afternoon
into the evening where training storms track over the same areas.
The eastward moving convection is expected to move faster towards
the east than the storms can backbuild, so the trailing line
responsible for the worst flooding should gradually shift east as
well. The storms could persist as long as until midnight in the
Florida Panhandle, but most guidance has it moving on and
dissipating earlier in the evening. Regardless, with potential for
multiple inch per hour rainfall rates with numerous storms through
the day tracking over the same areas, the storm total rainfall in
these areas is likely to pile up very quickly. Guidance suggests
rainfall totals in many areas of the High Risk could exceed 12
inches, though local amounts could approach 20 inches.

Widespread and potentially life threatening flash flooding is
likely as a result of these double-digit rainfall numbers. Urban
areas that could be impacted from New Orleans (in a higher-end
Moderate Risk), Mobile, and Pensacola could see life-threatening
flash flooding occur as a result. Everyone should heed the advice
of local authorities as warnings are issued.

Across central Alabama into northern Georgia, storm coverage and
intensity of the strongest cells are expected to be a bit lower,
but antecedent soil conditions remain nearly saturated. Multiple
hours of moderate to at times heavy rain are expected up as far
north as Birmingham and northeast as Atlanta. The Moderate Risk for
these areas remains in place with few changes. An eastward
expansion of the Moderate Risk in west-central Georgia was also
made.

...Ohio/Tennessee Valleys...

A cold front pushing south across the Ohio Valley today will run
into the northern extent of the deep plume of tropical moisture
associated with the remnants of Arthur. With daytime heating, the
clashing of air masses along the front will result in numerous
showers and thunderstorms developing along the front, which will
likely be along the KY/TN border, extending ENE into eastern
Kentucky and southern West Virginia. The storms will be in a
favorable environment for training as the plume of moisture tracks
parallel to the front as well. A shortwave trough will help the
front advance south and east across the area more quickly this
evening through tonight, which should end any backbuilding and
training from the afternoon and allow everything to progress
eastward, ending the flooding threat.

...Southwestern Oklahoma into North Texas...

Overnight tonight, an MCS is expected to develop across
southwestern Oklahoma and north Texas in response to both proximity
to the dry line, deep tropical moisture with PWATs approaching 2
inches, and a developing low over West Texas, encouraging the
formation of a low level jet into the storms. Given this is a
smaller feature than the remnants of Arthur to the east, the CAMs
are struggling much more with where and how long the storms in the
area will form, and where they will track. Most likely the storms
will remain along the Red River/OK-TX border. The inherited Slight
covering most of the rest of Oklahoma into Arkansas was dropped to
a Marginal as this MCS should remain well separated from the rains
with Arthur to the east, with little rain in between.

Wegman
=20

Day 2
Valid 12Z Fri Jun 19 2026 - 12Z Sat Jun 20 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR THE CENTRAL
GULF COAST...

...2030 UTC Update...

The prior forecast reasoning remains on track with the greatest
concern focused on where additional rainfall Friday may overlap
some of the torrential totals seen across the central Gulf Coast
into the Southeast on Thursday. Some instances of flash flooding
may remain ongoing as well. The now available 12Z hi-res guidance
supports the greatest risk of additional rainfall of 1-3", locally
4-6", across much of the inherited Moderate Risk area. Some minor
areal expansions where made to the northern extent of the moderate
across southern Alabama and Mississippi based on the latest
guidance, as well as to the southwest from coastal Mississippi
into southeastern Louisiana where some of the heaviest 24 hour
totals (MRMS estimated 6-10") had occurred through Thursday
afternoon. There was also a signal in the guidance for some similar
heavier totals further west across portions of western Louisiana.
However, most of this region did not see rainfall over the past day
and thus feel comfortable retaining the risk as a higher-end
Slight for now. Another more isolated but significant area of
concern will be if any rainfall overlaps portions of east-central
Louisiana where extreme rainfall of over 24" in the past 24 hours
has been estimated by MRMS.

Putnam

...Previous Discussion...

...Southeast...

While the plume of extreme moisture associated with the remnants of
Arthur will be exiting the Carolina coast at the start of the
period, deep tropical moisture will remain entrenched over much of
the Southeast on Friday. A cold front that tracked over the Ohio
Valley on Day 1/Thursday will continue edging southward into the
Southeast, bringing much drier air and relief to areas behind it.
Unfortunately ahead of it, the air mass will remain soupy. The
moisture off the Gulf will have turned eastward along the front on
Friday, which will do a couple things: 1) It will not prevent the
front from making more southward progress, as opposed to a
southerly low level jet which would actively work against a
southward moving front. 2) It will create a more unidirectional
wind flow through the depth of the atmosphere, which will support faster-moving, but training storms along the front. In addition to
any MCSs which could form in the soupy air mass early in the
morning, potentially multiple lines of storms will track
southeastward along the front into the area that just was hit with
Arthur's remnants the previous day. Thus, the Moderate Risk for
this area remains in effect. Expected rainfall for most areas will
generally stay between 1-3 inches on average, so the rainfall
amounts expected on Friday will pale in comparison to today.
However, given the expected flooding that will very much still be
ongoing on Friday, the addition of 1-3 inches of rain with locally
higher amounts where storm training persists longest over these
same areas still raised the flooding threat in the area to the
Moderate Risk category. Changes in where the heaviest rains
today/Day 1 occur may result in shifts of the Moderate Risk,
particularly if the heaviest expected rains occur further south and
west into Mississippi and eastern Louisiana. A few of the CAMs
models are hinting at that possibility.

...Southern Plains...

Across a large swath of Texas on Friday, multiple MCSs may impact
much of the state. On Friday morning, lingering MCSs from Oklahoma
and the Slight Risk on Day 1 may be ongoing into north-central
Texas Friday morning, including into the Metroplex. Widely
scattered instances of flash flooding will be possible with that.
More coverage of storms are expected Friday night. The typical
strengthening MCS will advect extreme instability and moisture over
all of the eastern half of the state. As storms form and organize
into MCSs, the potential for additional instances of flash flooding
will increase. There is considerable uncertainty as to where they
form and how they track, so a large swath of eastern Texas was
included in a Slight Risk, especially down towards San Antonio and
Houston, which have been impacted with heavy rains in recent days,
and soils remain wetter than normal.

Wegman
=20

Day 3
Valid 12Z Sat Jun 20 2026 - 12Z Sun Jun 21 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE CENTRAL PLAINS AND MISSOURI VALLEY...

...Central Plains and Missouri Valley...

A large area of heavy rain associated with a developing MCS
starting Saturday afternoon and continuing into Saturday night is
expected to bring widespread heavy rainfall across portions of the
central Plains into the Missouri Valley with the greatest threat
currently expected across southeastern Nebraska, northeastern
Kansas, and far northwestern Missouri/southwestern Iowa. Storms
are expected to initiate Saturday afternoon with peak heating. An
LLJ of southeasterly flow will pump deep Gulf moisture up the
Plains through the day. A developing surface low and upper level
shortwave strengthening the low over Colorado will eject into the
Plains. This will force the dryline to race eastward in response.
The warm front associated with the low and the dry line will uplift
the deep moisture, resulting in widespread shower and thunderstorm
development. These storms are expected to grow upscale into an
expansive, organized convective system into the evening and
overnight hours that will then track southeasterly across the risk
area. The latest deterministic guidance shows areal average
rainfall totals along the expected path of the MCS in the 2-3"
range with locally higher amounts of 4-6", more than sufficient to
lead to scattered and potentially widespread flash flooding, which
has prompted an upgrade to a Moderate Risk. As is usually the case
with convective systems the exact path and duration will be
determined by more mesoscale details than the guidance can
typically pin down at this time frame, so some areal modification
and possible expansion of the Moderate Risk will be likely over the
next couple of days. The most likely area for expansion would be
further to southeast into more of western Missouri and east- central/southeastern Kansans. However, given the noted uncertainty
with the evolution of these types of systems at this timeframe,
have limited the extent of the risk area to also overlap where the
greatest support/confidence is shown by the ensemble
mean/probabilistic guidance.

...Southeast...

An MCS tracking from the Ozarks following the same front that
entered interior portions of the Southeast as a cold front on
Friday will help that same front now retreat as a warm front on
Saturday. Heavy rains are expected Saturday morning over the Slight
Risk area from northern Mississippi to southern Alabama as storms
track southeastward along the retreating front. Daytime heating
will likely support additional clusters of storms into the
afternoon in these areas. The heaviest rains over the most
widespread area will be Saturday morning in northern Mississippi.
They will be less organized as they move into southern Alabama
Saturday afternoon, but given the prior day's expected rains in
these same areas, the Slight Risk includes southern Alabama as
well. Rainfall totals will likely be more limited than they have
compared to the prior days but the region will remain more
susceptible to additional instances of flash flooding given the
heavy rainfall received from precipitation associated with the
remnants of T.S. Arthur.

Putnam/Wegman
=20

Day 4 and Day 5
Valid 12Z Sun Jun 21 2026 - 12Z Tue Jun 23 2026=20

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM PORTIONS OF=20
THE OZARKS THROUGH THE MIDWEST AND INTO THE UPPER OHIO VALLEY...=20

2030Z Update...=20

Maintained the Slight risk in the Day 4 period and the Marginal=20
risk on Day 5 with few changes. The wave coming out of the Plains=20
and crossing into the Midwest remains the primary focus for heavy=20
to excessive rainfall on Sunday into early Monday. Some differences
linger in latitude of the axis of heaviest rainfall...but=20
probabilities were comparable with the overnight guidance.=20
Likewise...the previously issued outlook was still generally=20
captured the axis of heavier rainfall that could result in heavy to
potentially excessive rainfall on Monday. So changes tended to be=20
few.=20

Bann=20

Previous Discussion...=20

Day 4...=20
By the start of the day 4 forecast period a potent shortwave and=20
related surface low are expected to eject eastward out of the=20
central Plains into the Midwest. There will also be a trailing=20
frontal boundary extending into the southern Plains to add a focus=20
for additional thunderstorms. There remains some uncertainty=20
regarding the speed and latitude of these features, but PWs above=20
the 90th climatological percentile (per the 00z GEFS) overlapping=20
with soils likely still recovering from recent heavy rain in the=20
Midwest will lead to at least scattered flash flooding concerns.=20
NBM probabilities for at least 2" are between 30-55% and cover much
of the SLGT risk area. Locally higher totals are likely given the=20
convective environment. The progressive nature of these storms may=20
end up limiting the severity of flash flood impacts, but a MDT risk
upgrade is possible should training/back-building elements become=20
more obvious in the short range updates. This is especially the=20
case given the sensitivity of the affected regions to additional=20 rainfall.=20

Day 5...=20

The shortwave and low pressure on day 4 is=20
forecast to continue east towards the Mid-Atlantic and Northeast,=20
with additional uncertainties in latitude and speed. Additionally,=20 thunderstorms should reform along the attached frontal boundary=20
extending westward across the Tennessee Valley and into the=20
southern Plains. At the moment most convection appears scattered in
nature and low confidence in placement of heavier QPF. Therefore,=20
a MRGL risk is highlighted and will be refined in future updates.=20
Additional thunderstorm activity is likely into the High Plains,=20
with uncertainty surrounding the impact of a nearby southern Canada
upper low on thunderstorm activity in the northern High Plains.=20

Snell
=20

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!4adtx20aCGyON-cmdZW9JHaostsHy9raPTOgPJDmfNhK= iY5kw-21otXh490trH8DI0CNb740fV9BPkyla8rbfxRSQNU$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!4adtx20aCGyON-cmdZW9JHaostsHy9raPTOgPJDmfNhK= iY5kw-21otXh490trH8DI0CNb740fV9BPkyla8rb5Iftz2Y$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!4adtx20aCGyON-cmdZW9JHaostsHy9raPTOgPJDmfNhK= iY5kw-21otXh490trH8DI0CNb740fV9BPkyla8rbWn_44Kc$=20



$$

=3D =3D =3D
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--- SBBSecho 3.28-Linux
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FOUS30 KWBC 190053
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
853 PM EDT Thu Jun 18 2026

Day 1
Valid 01Z Fri Jun 19 2026 - 12Z Fri Jun 19 2026

...THERE IS A HIGH RISK OF EXCESSIVE RAINFALL FOR PARTS OF THE
CENTRAL GULF COAST...

...WIDESPREAD AND LIFE THREATENING FLASH FLOODING LIKELY INTO
TONIGHT FOR THE CENTRAL GULF COAST...

01Z Update...
The most active convection with 2+ inch per hour rainfall rates
have pushed into parts of southern Alabama as of early this
evening and the western portion of the High Risk area was shifted
eastward as well. However...the western portion of the Slight and
Marginal areas were largely left in place where satellite imagery
was showing convection reigniting along a boundary across the
central portion of Louisiana that extended into Mississippi. High
resolution CAMS were not terribly enthusiastic about additional
development there but maintained the lower-categories in the ERO
to account for the possibility that the convection builds farther
south. No changes needed to the Slight risk area farther west in
Texas where CAMs still develop convection related to the low level
jet nor to the Marginal in parts of Arizona and New Mexico. The
Marginal risk in New England was removed as rain continued to move
out of the area.

Bann
...1600 UTC Update...
A widespread and life-threatening flash flood event is underway
across the central Gulf Coast and will continue to expand
northeastward deeper into the Southeast throughout the day. Flash
flood emergencies have already been issued both in southeastern and
central LA as well as southern Mississippi where bands of
backbuilding, training thunderstorms have already lead to MRMS
estimated rainfall totals of 9-11" (see WPC MPD #450 for more
details). Torrential rainfall is expected to continue throughout
the day with these ongoing storms as well as additional bands of
thunderstorms supported by a surface low associated with the
remnants of Tropical Storm Arthur, an impressive ~40-50 kt low
level jet off the Gulf, and daily-record level PWATS over 2". Some
modest adjustments were made to the inherited outlook based on
ongoing thunderstorms and the latest 12Z hi-res guidance including
a westward expansion of the High Risk to central Louisiana where
ongoing life-threatening flash flooding is occurring. A slight
northeastward expansion was also included across southern
Mississippi and Alabama given moderate to high probabilities from
the HREF of 5-8"+ of rainfall. Guidance in general has suggested a northeastward expansion of the flash flood risk bringing heightened
concern to southwestern to central Georgia as well as further
north into the southern Appalachians.
Elsewhere, the Slight Risk over portions of the southern
Plains/Texas was also expanded based on the latest 12Z hi-res
guidance. Thunderstorms are expected to develop later this evening
and into the overnight hours in vicinity of a wave of low pressure
along an approaching cold front and southward along the dryline.
Sporadic/slow storm motions and clustering of storms will support
locally heavy rainfall, especially if the collective
clustering/merging of cold pools can result in more organized
complexes as suggested by some of the hi-res guidance. This
includes both along the Red River Valley, where a Slight Risk is
already in place, as well as further south along the dryline into
the Texas Hill Country where the Slight Risk has been expanded.
Some of the latest hi-res guidance (including the RRFS) is more
bullish on the potential for heavier rainfall spreading southward
given expected storm motions and potential for a more organized
complex to develop.
Another round of thunderstorms is expected today over portions of
Arizona and New Mexico where some locally heavy rainfall/isolated
flash flooding will be possible given heightened moisture in place.
Most storms will likely be diurnally driven along the more complex
terrain. Increased moist southerly flow off the Atlantic into
interior New England/Upstate New York ahead of an approaching low
pressure system will also bring the threat for some locally heavy
rainfall (1-3" totals) and isolated flash flooding.
Putnam
...Previous Discussion...
...Southeast...
The remnants of Post Tropical Cyclone Arthur are moving into the
Central Gulf Coast this morning. While the cyclone center may have
dissipated, the moisture plume and associated rainfall shield most
certainly have not. Rainfall moving into southeastern Louisiana
right now are producing rates to 3 inches per hour. These kinds of
rainfall rates are expected to continue with the strongest cells
for much of the day today across the central Gulf Coast. An
impressive 50 kt low level jet at 850 is advecting very deep
tropical moisture into the coast. This is pushing PWATs to over 2.6
inches. Meanwhile instability over the Gulf is up to 4,000 J/kg.
This is supporting very efficient cells capable of multiple inch
per hour rates to the east of the remnant circulation center.
Multiple waves of storms will track south to north across eastern
Louisiana into southern Mississippi this morning. The area has been
hard hit with heavy rain in recent days, so larger rivers are
already flooding, and soils are nearly saturated, so nearly all of
the heavy rainfall is expected to convert to runoff, resulting in
more significant river, stream, and creek rises though the morning.
The eastern side of the plume of moisture will spawn additional
numerous thunderstorms into southern Alabama and the Florida
Panhandle through midday. The storm organization is expected to
change a bit into the afternoon with peak heating. To the west
across Mississippi and Louisiana, backbuilding and training
convection is expected to form into 1 or 2 nearly stationary lines,
as the individual cells embedded within train towards the east
along the line. Meanwhile, over Alabama, multiple lines of eastward
moving lines of storms will get the flooding and heavy rainfall
started as early as mid-morning. The western end of the line in
LA/MS will become the trailing storms on the southwest end of the
MCS associated with post tropical cyclone Arthur. This line will
very slowly drift southeastward towards the Gulf Coast, likely
impacting Mobile and eventually the Pensacola area, as well as
points north. This will result in multiple hours from mid-afternoon
into the evening where training storms track over the same areas.
The eastward moving convection is expected to move faster towards
the east than the storms can backbuild, so the trailing line
responsible for the worst flooding should gradually shift east as
well. The storms could persist as long as until midnight in the
Florida Panhandle, but most guidance has it moving on and
dissipating earlier in the evening. Regardless, with potential for
multiple inch per hour rainfall rates with numerous storms through
the day tracking over the same areas, the storm total rainfall in
these areas is likely to pile up very quickly. Guidance suggests
rainfall totals in many areas of the High Risk could exceed 12
inches, though local amounts could approach 20 inches.
Widespread and potentially life threatening flash flooding is
likely as a result of these double-digit rainfall numbers. Urban
areas that could be impacted from New Orleans (in a higher-end
Moderate Risk), Mobile, and Pensacola could see life-threatening
flash flooding occur as a result. Everyone should heed the advice
of local authorities as warnings are issued.
Across central Alabama into northern Georgia, storm coverage and
intensity of the strongest cells are expected to be a bit lower,
but antecedent soil conditions remain nearly saturated. Multiple
hours of moderate to at times heavy rain are expected up as far
north as Birmingham and northeast as Atlanta. The Moderate Risk for
these areas remains in place with few changes. An eastward
expansion of the Moderate Risk in west-central Georgia was also
made.
...Ohio/Tennessee Valleys...
A cold front pushing south across the Ohio Valley today will run
into the northern extent of the deep plume of tropical moisture
associated with the remnants of Arthur. With daytime heating, the
clashing of air masses along the front will result in numerous
showers and thunderstorms developing along the front, which will
likely be along the KY/TN border, extending ENE into eastern
Kentucky and southern West Virginia. The storms will be in a
favorable environment for training as the plume of moisture tracks
parallel to the front as well. A shortwave trough will help the
front advance south and east across the area more quickly this
evening through tonight, which should end any backbuilding and
training from the afternoon and allow everything to progress
eastward, ending the flooding threat.
...Southwestern Oklahoma into North Texas...
Overnight tonight, an MCS is expected to develop across
southwestern Oklahoma and north Texas in response to both proximity
to the dry line, deep tropical moisture with PWATs approaching 2
inches, and a developing low over West Texas, encouraging the
formation of a low level jet into the storms. Given this is a
smaller feature than the remnants of Arthur to the east, the CAMs
are struggling much more with where and how long the storms in the
area will form, and where they will track. Most likely the storms
will remain along the Red River/OK-TX border. The inherited Slight
covering most of the rest of Oklahoma into Arkansas was dropped to
a Marginal as this MCS should remain well separated from the rains
with Arthur to the east, with little rain in between.
Wegman
=20

Day 2
Valid 12Z Fri Jun 19 2026 - 12Z Sat Jun 20 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR THE CENTRAL
GULF COAST...

...2030 UTC Update...

The prior forecast reasoning remains on track with the greatest
concern focused on where additional rainfall Friday may overlap
some of the torrential totals seen across the central Gulf Coast
into the Southeast on Thursday. Some instances of flash flooding
may remain ongoing as well. The now available 12Z hi-res guidance
supports the greatest risk of additional rainfall of 1-3", locally
4-6", across much of the inherited Moderate Risk area. Some minor
areal expansions where made to the northern extent of the moderate
across southern Alabama and Mississippi based on the latest
guidance, as well as to the southwest from coastal Mississippi
into southeastern Louisiana where some of the heaviest 24 hour
totals (MRMS estimated 6-10") had occurred through Thursday
afternoon. There was also a signal in the guidance for some similar
heavier totals further west across portions of western Louisiana.
However, most of this region did not see rainfall over the past day
and thus feel comfortable retaining the risk as a higher-end
Slight for now. Another more isolated but significant area of
concern will be if any rainfall overlaps portions of east-central
Louisiana where extreme rainfall of over 24" in the past 24 hours
has been estimated by MRMS.

Putnam

...Previous Discussion...

...Southeast...

While the plume of extreme moisture associated with the remnants of
Arthur will be exiting the Carolina coast at the start of the
period, deep tropical moisture will remain entrenched over much of
the Southeast on Friday. A cold front that tracked over the Ohio
Valley on Day 1/Thursday will continue edging southward into the
Southeast, bringing much drier air and relief to areas behind it.
Unfortunately ahead of it, the air mass will remain soupy. The
moisture off the Gulf will have turned eastward along the front on
Friday, which will do a couple things: 1) It will not prevent the
front from making more southward progress, as opposed to a
southerly low level jet which would actively work against a
southward moving front. 2) It will create a more unidirectional
wind flow through the depth of the atmosphere, which will support faster-moving, but training storms along the front. In addition to
any MCSs which could form in the soupy air mass early in the
morning, potentially multiple lines of storms will track
southeastward along the front into the area that just was hit with
Arthur's remnants the previous day. Thus, the Moderate Risk for
this area remains in effect. Expected rainfall for most areas will
generally stay between 1-3 inches on average, so the rainfall
amounts expected on Friday will pale in comparison to today.
However, given the expected flooding that will very much still be
ongoing on Friday, the addition of 1-3 inches of rain with locally
higher amounts where storm training persists longest over these
same areas still raised the flooding threat in the area to the
Moderate Risk category. Changes in where the heaviest rains
today/Day 1 occur may result in shifts of the Moderate Risk,
particularly if the heaviest expected rains occur further south and
west into Mississippi and eastern Louisiana. A few of the CAMs
models are hinting at that possibility.

...Southern Plains...

Across a large swath of Texas on Friday, multiple MCSs may impact
much of the state. On Friday morning, lingering MCSs from Oklahoma
and the Slight Risk on Day 1 may be ongoing into north-central
Texas Friday morning, including into the Metroplex. Widely
scattered instances of flash flooding will be possible with that.
More coverage of storms are expected Friday night. The typical
strengthening MCS will advect extreme instability and moisture over
all of the eastern half of the state. As storms form and organize
into MCSs, the potential for additional instances of flash flooding
will increase. There is considerable uncertainty as to where they
form and how they track, so a large swath of eastern Texas was
included in a Slight Risk, especially down towards San Antonio and
Houston, which have been impacted with heavy rains in recent days,
and soils remain wetter than normal.

Wegman
=20

Day 3
Valid 12Z Sat Jun 20 2026 - 12Z Sun Jun 21 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE CENTRAL PLAINS AND MISSOURI VALLEY...

...Central Plains and Missouri Valley...

A large area of heavy rain associated with a developing MCS
starting Saturday afternoon and continuing into Saturday night is
expected to bring widespread heavy rainfall across portions of the
central Plains into the Missouri Valley with the greatest threat
currently expected across southeastern Nebraska, northeastern
Kansas, and far northwestern Missouri/southwestern Iowa. Storms
are expected to initiate Saturday afternoon with peak heating. An
LLJ of southeasterly flow will pump deep Gulf moisture up the
Plains through the day. A developing surface low and upper level
shortwave strengthening the low over Colorado will eject into the
Plains. This will force the dryline to race eastward in response.
The warm front associated with the low and the dry line will uplift
the deep moisture, resulting in widespread shower and thunderstorm
development. These storms are expected to grow upscale into an
expansive, organized convective system into the evening and
overnight hours that will then track southeasterly across the risk
area. The latest deterministic guidance shows areal average
rainfall totals along the expected path of the MCS in the 2-3"
range with locally higher amounts of 4-6", more than sufficient to
lead to scattered and potentially widespread flash flooding, which
has prompted an upgrade to a Moderate Risk. As is usually the case
with convective systems the exact path and duration will be
determined by more mesoscale details than the guidance can
typically pin down at this time frame, so some areal modification
and possible expansion of the Moderate Risk will be likely over the
next couple of days. The most likely area for expansion would be
further to southeast into more of western Missouri and east- central/southeastern Kansans. However, given the noted uncertainty
with the evolution of these types of systems at this timeframe,
have limited the extent of the risk area to also overlap where the
greatest support/confidence is shown by the ensemble
mean/probabilistic guidance.

...Southeast...

An MCS tracking from the Ozarks following the same front that
entered interior portions of the Southeast as a cold front on
Friday will help that same front now retreat as a warm front on
Saturday. Heavy rains are expected Saturday morning over the Slight
Risk area from northern Mississippi to southern Alabama as storms
track southeastward along the retreating front. Daytime heating
will likely support additional clusters of storms into the
afternoon in these areas. The heaviest rains over the most
widespread area will be Saturday morning in northern Mississippi.
They will be less organized as they move into southern Alabama
Saturday afternoon, but given the prior day's expected rains in
these same areas, the Slight Risk includes southern Alabama as
well. Rainfall totals will likely be more limited than they have
compared to the prior days but the region will remain more
susceptible to additional instances of flash flooding given the
heavy rainfall received from precipitation associated with the
remnants of T.S. Arthur.

Putnam/Wegman
=20

Day 4 and Day 5

Valid 12Z Sun Jun 21 2026 - 12Z Tue Jun 23 2026
...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM PORTIONS OF
THE OZARKS THROUGH THE MIDWEST AND INTO THE UPPER OHIO VALLEY...
2030Z Update...
Maintained the Slight risk in the Day 4 period and the Marginal
risk on Day 5 with few changes. The wave coming out of the Plains
and crossing into the Midwest remains the primary focus for heavy
to excessive rainfall on Sunday into early Monday. Some differences
linger in latitude of the axis of heaviest rainfall...but
probabilities were comparable with the overnight guidance. Likewise...the previously issued outlook was still generally captured the axis of
heavier rainfall that could result in heavy to potentially
excessive rainfall on Monday. So changes tended to be few.
Bann
Previous Discussion...
Day 4... By the start of the day 4 forecast period a potent
shortwave and related surface low are expected to eject eastward
out of the central Plains into the Midwest. There will also be a
trailing frontal boundary extending into the southern Plains to add
a focus for additional thunderstorms. There remains some
uncertainty regarding the speed and latitude of these features, but
PWs above the 90th climatological percentile (per the 00z GEFS)
overlapping with soils likely still recovering from recent heavy
rain in the Midwest will lead to at least scattered flash flooding
concerns. NBM probabilities for at least 2" are between 30-55% and
cover much of the SLGT risk area. Locally higher totals are likely
given the convective environment. The progressive nature of these
storms may end up limiting the severity of flash flood impacts, but
a MDT risk upgrade is possible should training/back-building
elements become more obvious in the short range updates. This is
especially the case given the sensitivity of the affected regions
to additional rainfall.
Day 5... The shortwave and low pressure on day 4 is forecast to
continue east towards the Mid-Atlantic and Northeast, with
additional uncertainties in latitude and speed. Additionally,
thunderstorms should reform along the attached frontal boundary
extending westward across the Tennessee Valley and into the
southern Plains. At the moment most convection appears scattered in
nature and low confidence in placement of heavier QPF. Therefore, a
MRGL risk is highlighted and will be refined in future updates.
Additional thunderstorm activity is likely into the High Plains,
with uncertainty surrounding the impact of a nearby southern Canada
upper low on thunderstorm activity in the northern High Plains.
Snell
=20

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!_tIhNSvkIPY35ZrORHtsU5rQjz04YmEknmze9RBXYKI_= NxXsqe6y0wOc39sqIGZ6Y6of0VBoQWVhHHQGhEPANmaslVE$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!_tIhNSvkIPY35ZrORHtsU5rQjz04YmEknmze9RBXYKI_= NxXsqe6y0wOc39sqIGZ6Y6of0VBoQWVhHHQGhEPAkwy3hzY$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!_tIhNSvkIPY35ZrORHtsU5rQjz04YmEknmze9RBXYKI_= NxXsqe6y0wOc39sqIGZ6Y6of0VBoQWVhHHQGhEPAZ1rEV68$=20



$$

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FOUS30 KWBC 190728
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
328 AM EDT Fri Jun 19 2026

Day 1
Valid 12Z Fri Jun 19 2026 - 12Z Sat Jun 20 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL IN EFFECT FOR
PARTS OF THE CENTRAL GULF COAST REGION...

...Central Gulf Coast States...

Lingering flood impacts following the deluge over the last 24
hours will be exacerbated by additional rounds of slow-moving
convection today from central MS and eastern LA to the FL Panhandle
and far southwest GA. Low-to-mid level convergence will extend in
a west-east orientation just to the north of the Gulf Coast and
remain a focus for broken areas of showers and thunderstorms
throughout the day. These storms will tap into PWs above 2" and
remain relatively slow-moving with westerly convergent 850mb flow
less than 15 kts, leading to hourly rates of 2-3"/hr. Activity will
likely be ongoing across the region at 12z and pulse throughout
the day and into the overnight period. 00z HREF probabilities for
at least 3" per 6-hrs start the day 1 period as high as 60% across
southern AL and the FL Panhandle before becoming more scattered in
nature and lowering to around 30% for the overnight period. The
primary factor for maintaining the MDT risk is the fact that these
storms are likely to overlap with an area that recently received
widespread 4-8" rainfall totals (locally over 12") and soils are
easily overcome when rainfall rates exceed 2"/hr. This will lead to
additional scattered flash flood concerns on top of ongoing flood
impacts and recovery efforts.

...Southern Plains to the Upper Texas Coast...

Scattered flash flooding is also a concern from southern OK into
much of central and eastern TX today as thunderstorm activity
begins early this morning and gradually meanders east with time
through tonight. Vast amounts of uncertainty exist with the
mesoscale details surrounding the excessive rainfall forecast in
this area, particularly for being a day 1 forecast, but PWs
near/slightly above 2" and widespread dew points into the upper 70s
and low 80s point to an environment ripe for intense rainfall
rates. As convection develops early this morning the expectation is
for an MCV or multiple MCVs to spawn ahead of an approaching weak
shortwave and within a building ridge over the south-central U.S..
This weak steering pattern will lead to conditions where MCV
location and outflow boundaries could drive the convective mode.
Even if thunderstorms remain mostly progressive after cold pools
develop, intense rainfall rates of 2-3" are possible throughout the
Southern Plains into eastern TX and the ArkLaTex. One area of
focus to monitor into the overnight period into Saturday morning
will be across eastern TX into central LA where a frontal boundary
is forecast to drape and potential interact with a weak surface
low or remnant MCV. Several CAMs indicate more widespread
thunderstorm activity around 12z Sat. here or just to the south
across southeast TX as the nocturnal low-level flow increases
towards the frontal boundary. 00z HREF neighborhood probs for at
least 3" per 6-hrs are generally around 30% here, but REFS probs
are much higher (60%) and farther south along the upper TX
coastline. Thus, a large SLGT risk is in effect for this region to
highlight the widely scattered/uncertain nature of thunderstorms,
but while also likely containing intense rainfall rates capable of
flash flood impacts.

Snell
=20

Day 2
Valid 12Z Sat Jun 20 2026 - 12Z Sun Jun 21 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL ACROSS PARTS OF
THE CENTRAL PLAINS AND MISSOURI VALLEY...

...Central Plains and Missouri Valley...

A large area of heavy rain associated with a developing MCS
starting Saturday afternoon and continuing into Saturday night is
expected to bring widespread heavy rainfall across portions of the
central Plains into the Missouri Valley with the greatest threat
currently expected across southeastern Nebraska, northeastern
Kansas, and far northwestern Missouri/southwestern Iowa. Storms
are expected to initiate Saturday afternoon with peak heating over
the central High Plains and ahead of a racing shortwave crossing
the Rockies. Meanwhile, a LLJ of southeasterly flow will pump deep
Gulf moisture up the Plains through the day. This will force the
dryline to race eastward in response. The warm front associated
with the low and the dry line will uplift the deep moisture,
resulting in widespread shower and thunderstorm development. These
storms are expected to grow upscale into an expansive, organized
convective system into the evening and overnight hours that will
then track southeasterly across the risk area.

The latest deterministic guidance shows areal average rainfall
totals along the expected path of the MCS in the 2-3" range with
locally higher amounts of 4-6", more than sufficient to lead to
scattered and potentially widespread flash flooding, which has
prompted the level 3/4 Moderate Risk. As is usually the case with
convective systems the exact path and duration will be determined
by more mesoscale details than the guidance can typically pin down
at this time frame, so some areal modification and possible
expansion of the Moderate Risk will be likely over the next couple
of days. The most likely area for expansion would be further to
southeast into more of western Missouri and east-
central/southeastern Kansas. However, given the noted uncertainty
with the evolution of these types of systems at this timeframe,
have limited the extent of the risk area to also overlap where the
greatest support/confidence is shown by the ensemble
mean/probabilistic guidance.

...Eastern Texas through the Central Gulf Coast...

One more day of scattered slow-moving storms is expected on
Saturday across the Deep South between eastern TX and southern
AL/FL Panhandle. The lingering frontal boundary draped north of the
Gulf Coast will begin to lift north during the day and leave
convection widely scattered, but more focused activity is likely
during the morning hours as high pressure over the Tennessee Valley
keeps the thermal/moisture gradient rather sharp and focuses
ongoing thunderstorm activity within PWs above 2". Lingering MCV(s)
from the day 1 period across eastern TX and the Lower Mississippi
Valley could also add locations for more organized thunderstorm
activity. The soils in this region also remain extremely saturated
and sensitive to additional intense rainfall rates, leading to the
potential for scattered instances of flash flooding on Saturday and
the SLGT risk of excessive rainfall.

Snell
=20

Day 3
Valid 12Z Sun Jun 21 2026 - 12Z Mon Jun 22 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM EASTERN
OKLAHOMA AND THE OZARKS THROUGH MUCH OF THE MIDWEST AND OHIO VALLEY...

...Midwest...

By the start of the day 3 forecast period a potent shortwave and
related surface low are expected to eject eastward out of the
central Plains into the Midwest. There remains some uncertainty
regarding the speed and latitude of these features, but PWs above
the 90th climatological percentile (per the 00z GEFS) overlapping
with soils likely still recovering from recent heavy rain in the
Midwest will lead to at least scattered flash flooding concerns.
NBM probabilities for at least 2" are very high (between 60-80%)
and cover much of the northern SLGT risk area from MO/IA to OH.
Locally higher totals are likely given the convective environment.
The progressive nature of these storms may end up limiting the
severity of flash flood impacts, but a MDT risk upgrade is possible
should training/back- building elements become more obvious in the
short range updates, particularly along the leading warm front
ahead of the primary surface low.

...Southern Plains, Ozarks, and Lower Ohio Valley...

The setup on Sunday could lead to a southern secondary axis of
heaviest QPF and flash flooding impacts. The southern end of the
Saturday night thunderstorm complex/MCS is likely to sink
southeastward near a trailing cold front and impact areas near the
Ozarks early Sunday. Then, the expectation is for reforming
scattered convection during peak daytime heating and reorganization
of thunderstorms overnight Sunday associated with the LLJ to span
from OK to the Lower Ohio Valley, including northern AR, southern
MO, and western TN/KY. This combines for guidance to currently
depict current QPF amounts of 2-4" and an average localized max of
6". There remains obvious mesoscale uncertainties at this stage,
but with Pws near the 90th climatological percentile and a
favorably oriented west- east frontal boundary, it's possible a MDT
risk upgrade may be needed once CAMs come into forecast range. For
the Lower Ohio Valley in particular, some guidance also highlights thunderstorms associated with the initial warm front lifting
northward, which could add yet another potential for slow-moving
repeating thunderstorms.

Snell
=20

Day 4 and Day 5

Valid 12Z Mon Jun 22 2026 - 12Z Wed Jun 24 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM PORTIONS OF
THE SOUTHERN PLAINS, LOWER MISSISSIPPI AND TENNESSEE VALLEYS, AND
CENTRAL APPALACHIANS ON DAY 4...

Day 4 continues to an active pattern through a good portion of the
CONUS, east of the Mississippi with a progressive trough axis
pushing through the Great Lakes and Northeast leading to periods of
moderate to heavy rainfall from the Ohio Valley into the Mid
Atlantic and Northeast. Areas of the Northeast are subject to
thunderstorm prospects with the best chance for flash flooding
likely to occur in the urban footprint from Philadelphia up to
Boston with an expansion inland to the Hudson Valley down through
eastern PA. Current probs off the latest ensembles and National
Blend indicate a large zone of 50-80% probs for >1" across the
aforementioned area above with deterministic outputs closer to
2-2.5" into parts of Southern New England. MRGL risk inherited
remains in effect, but there's potential here for an upgrade as we
move closer to the D4 window, but want to see more of the CAMs to
make that decision.

Across the Southern U.S., heavy precipitation will preclude another
round of convection forming along a quasi-stationary front draped
from the Southern High Plains to the Southeastern CONUS. Probs for

1" are highest in-of the areas of Eastern OK into the Lower

Mississippi and southwestern Tennessee Valleys. Elevated theta_E's
and PWAT anomalies +2 dev. or greater indicate a formidable
environment capable of continued heavy rain potential that will
likely produce rainfall of 2-4", at least in some of the
thunderstorm activity that develops. The focal point along the
front will likely be where the heaviest rain will occur, or at
least be a low-level convergence mechanism that can enhance
regional convection. There's high enough confidence in the location
of convection for the D4 period to overlap with areas that will
have seen several inches the periods prior which led to an upgrade
to a SLGT risk positioned over portions of the Southern Plains
through parts of the Lower Mississippi and neighboring Tennessee
Valleys. The risk extends through the Smokey Mountains up into
parts of the Central Appalachians in eastern KY up into WV as the
convergence regime follows the frontal positioning over these
areas.

Day 5 is a transition period into a more typical summer time regime
for the CONUS with a longwave trough over the Northern U.S. and a
dome of mid and upper ridging positioning itself across the
Southwest. This will cause a persistent northwesterly flow pattern
across the Central and Southern High Plains over into the Lower
Mississippi Valley as progressive shortwave pulses eject out of the
Rockies and ride the prevailing northwesteries in place between the
ridge and trough. This highlights potential for MCS development and
flash flooding scenarios from the Front Range and points southeast
as the steering flow orients between the base of the trough and the northeastern flank of the ridge. This is historically projecting a
case of thunderstorm maturation and upscale growth over the area
between CO/KS down through OK/TX with potentially the Red River
Basin as a focus for thunderstorm activity. Eventually this ends up
migrating into the ArkLaTex and/or Lower Mississippi area which is
showing up in the QPF footprint on ensembles. With this becoming a
more stable signal in the global ensembles and aligning with the
NBM QPF output, a MRGL risk was added to the new D5 to account for
this potential evolution.

Kleebauer
=20

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!5YoEOmxHrStp70yidIrExb99j5MyYp5QdEjEpaVzJWEA= 18a-cRAug3JTQl0siPZUWxuPma2NPz8BBPetM8ryru2JZhc$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!5YoEOmxHrStp70yidIrExb99j5MyYp5QdEjEpaVzJWEA= 18a-cRAug3JTQl0siPZUWxuPma2NPz8BBPetM8ryW0ADAaU$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!5YoEOmxHrStp70yidIrExb99j5MyYp5QdEjEpaVzJWEA= 18a-cRAug3JTQl0siPZUWxuPma2NPz8BBPetM8ryidGR95M$=20



$$

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FOUS30 KWBC 191545
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1145 AM EDT Fri Jun 19 2026

Day 1
Valid 16Z Fri Jun 19 2026 - 12Z Sat Jun 20 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL IN EFFECT FOR
PORTIONS OF THE CENTRAL GULF COAST REGION...

...16Z Update...

No major changes were needed for the risk areas with this update.
Much of the expected rainfall is ongoing in the defined risk areas
across Texas, and for the MDT risk region, more widespread
scattered convection is expected to develop over the next few hours
with daytime heating. The convection appears unlikely to become
very organized, instead favoring pulse thunderstorms or small
clusters. Cell mergers appear to be the biggest threat when it
comes to localized renewed flash flooding this afternoon in the
Moderate Risk area across southern Alabama and Mississippi.

Elsewhere, a higher-end Slight has been issued for northern
Louisiana into northeast Texas for the ongoing very slow-moving
storms that are approaching Texarkana. These storms are expected to
continue building eastward into the afternoon, followed by a break
in the area for much of the overnight. Additional convection could
develop in the early morning hours.

The Slight over Georgia was expanded to near the coast for the
ongoing training storms in that area, which could persist into the
afternoon.

Finally, the Marginal Risk across the eastern Carolinas was dropped
with this update as the rain ongoing there pushes offshore and much
drier air replaces them, ending even a Marginal flooding threat
there.

Wegman

...Previous Discussion...

...Central Gulf Coast States...

Lingering flood impacts following the deluge over the last 24
hours will be exacerbated by additional rounds of slow-moving
convection today from central MS and eastern LA to the FL Panhandle
and far southwest GA. Low-to-mid level convergence will extend in
a west-east orientation just to the north of the Gulf Coast and
remain a focus for broken areas of showers and thunderstorms
throughout the day. These storms will tap into PWs above 2" and
remain relatively slow-moving with westerly convergent 850mb flow
less than 15 kts, leading to hourly rates of 2-3"/hr. Activity will
likely be ongoing across the region at 12z and pulse throughout
the day and into the overnight period. 00z HREF probabilities for
at least 3" per 6-hrs start the day 1 period as high as 60% across
southern AL and the FL Panhandle before becoming more scattered in
nature and lowering to around 30% for the overnight period. The
primary factor for maintaining the MDT risk is the fact that these
storms are likely to overlap with an area that recently received
widespread 4-8" rainfall totals (locally over 12") and soils are
easily overcome when rainfall rates exceed 2"/hr. This will lead to
additional scattered flash flood concerns on top of ongoing flood
impacts and recovery efforts.

...Southern Plains to the Upper Texas Coast...

Scattered flash flooding is also a concern from southern OK into
much of central and eastern TX today as thunderstorm activity
begins early this morning and gradually meanders east with time
through tonight. Vast amounts of uncertainty exist with the
mesoscale details surrounding the excessive rainfall forecast in
this area, particularly for being a day 1 forecast, but PWs
near/slightly above 2" and widespread dew points into the upper 70s
and low 80s point to an environment ripe for intense rainfall
rates. As convection develops early this morning the expectation is
for an MCV or multiple MCVs to spawn ahead of an approaching weak
shortwave and within a building ridge over the south-central U.S..
This weak steering pattern will lead to conditions where MCV
location and outflow boundaries could drive the convective mode.
Even if thunderstorms remain mostly progressive after cold pools
develop, intense rainfall rates of 2-3" are possible throughout the
Southern Plains into eastern TX and the ArkLaTex. One area of
focus to monitor into the overnight period into Saturday morning
will be across eastern TX into central LA where a frontal boundary
is forecast to drape and potential interact with a weak surface
low or remnant MCV. Several CAMs indicate more widespread
thunderstorm activity around 12z Sat. here or just to the south
across southeast TX as the nocturnal low-level flow increases
towards the frontal boundary. 00z HREF neighborhood probs for at
least 3" per 6-hrs are generally around 30% here, but REFS probs
are much higher (60%) and farther south along the upper TX
coastline. Thus, a large SLGT risk is in effect for this region to
highlight the widely scattered/uncertain nature of thunderstorms,
but while also likely containing intense rainfall rates capable of
flash flood impacts.

Snell
=20

Day 2
Valid 12Z Sat Jun 20 2026 - 12Z Sun Jun 21 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL ACROSS PARTS OF
THE CENTRAL PLAINS AND MISSOURI VALLEY...

...Central Plains and Missouri Valley...

A large area of heavy rain associated with a developing MCS
starting Saturday afternoon and continuing into Saturday night is
expected to bring widespread heavy rainfall across portions of the
central Plains into the Missouri Valley with the greatest threat
currently expected across southeastern Nebraska, northeastern
Kansas, and far northwestern Missouri/southwestern Iowa. Storms
are expected to initiate Saturday afternoon with peak heating over
the central High Plains and ahead of a racing shortwave crossing
the Rockies. Meanwhile, a LLJ of southeasterly flow will pump deep
Gulf moisture up the Plains through the day. This will force the
dryline to race eastward in response. The warm front associated
with the low and the dry line will uplift the deep moisture,
resulting in widespread shower and thunderstorm development. These
storms are expected to grow upscale into an expansive, organized
convective system into the evening and overnight hours that will
then track southeasterly across the risk area.

The latest deterministic guidance shows areal average rainfall
totals along the expected path of the MCS in the 2-3" range with
locally higher amounts of 4-6", more than sufficient to lead to
scattered and potentially widespread flash flooding, which has
prompted the level 3/4 Moderate Risk. As is usually the case with
convective systems the exact path and duration will be determined
by more mesoscale details than the guidance can typically pin down
at this time frame, so some areal modification and possible
expansion of the Moderate Risk will be likely over the next couple
of days. The most likely area for expansion would be further to
southeast into more of western Missouri and east-
central/southeastern Kansas. However, given the noted uncertainty
with the evolution of these types of systems at this timeframe,
have limited the extent of the risk area to also overlap where the
greatest support/confidence is shown by the ensemble
mean/probabilistic guidance.

...Eastern Texas through the Central Gulf Coast...

One more day of scattered slow-moving storms is expected on
Saturday across the Deep South between eastern TX and southern
AL/FL Panhandle. The lingering frontal boundary draped north of the
Gulf Coast will begin to lift north during the day and leave
convection widely scattered, but more focused activity is likely
during the morning hours as high pressure over the Tennessee Valley
keeps the thermal/moisture gradient rather sharp and focuses
ongoing thunderstorm activity within PWs above 2". Lingering MCV(s)
from the day 1 period across eastern TX and the Lower Mississippi
Valley could also add locations for more organized thunderstorm
activity. The soils in this region also remain extremely saturated
and sensitive to additional intense rainfall rates, leading to the
potential for scattered instances of flash flooding on Saturday and
the SLGT risk of excessive rainfall.

Snell
=20

Day 3
Valid 12Z Sun Jun 21 2026 - 12Z Mon Jun 22 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM EASTERN
OKLAHOMA AND THE OZARKS THROUGH MUCH OF THE MIDWEST AND OHIO VALLEY...

...Midwest...

By the start of the day 3 forecast period a potent shortwave and
related surface low are expected to eject eastward out of the
central Plains into the Midwest. There remains some uncertainty
regarding the speed and latitude of these features, but PWs above
the 90th climatological percentile (per the 00z GEFS) overlapping
with soils likely still recovering from recent heavy rain in the
Midwest will lead to at least scattered flash flooding concerns.
NBM probabilities for at least 2" are very high (between 60-80%)
and cover much of the northern SLGT risk area from MO/IA to OH.
Locally higher totals are likely given the convective environment.
The progressive nature of these storms may end up limiting the
severity of flash flood impacts, but a MDT risk upgrade is possible
should training/back- building elements become more obvious in the
short range updates, particularly along the leading warm front
ahead of the primary surface low.

...Southern Plains, Ozarks, and Lower Ohio Valley...

The setup on Sunday could lead to a southern secondary axis of
heaviest QPF and flash flooding impacts. The southern end of the
Saturday night thunderstorm complex/MCS is likely to sink
southeastward near a trailing cold front and impact areas near the
Ozarks early Sunday. Then, the expectation is for reforming
scattered convection during peak daytime heating and reorganization
of thunderstorms overnight Sunday associated with the LLJ to span
from OK to the Lower Ohio Valley, including northern AR, southern
MO, and western TN/KY. This combines for guidance to currently
depict current QPF amounts of 2-4" and an average localized max of
6". There remains obvious mesoscale uncertainties at this stage,
but with Pws near the 90th climatological percentile and a
favorably oriented west- east frontal boundary, it's possible a MDT
risk upgrade may be needed once CAMs come into forecast range. For
the Lower Ohio Valley in particular, some guidance also highlights thunderstorms associated with the initial warm front lifting
northward, which could add yet another potential for slow-moving
repeating thunderstorms.

Snell
=20

Day 4 and Day 5

Valid 12Z Mon Jun 22 2026 - 12Z Wed Jun 24 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM PORTIONS OF
THE SOUTHERN PLAINS, LOWER MISSISSIPPI AND TENNESSEE VALLEYS, AND
CENTRAL APPALACHIANS ON DAY 4...

Day 4 continues to an active pattern through a good portion of the
CONUS, east of the Mississippi with a progressive trough axis
pushing through the Great Lakes and Northeast leading to periods of
moderate to heavy rainfall from the Ohio Valley into the Mid
Atlantic and Northeast. Areas of the Northeast are subject to
thunderstorm prospects with the best chance for flash flooding
likely to occur in the urban footprint from Philadelphia up to
Boston with an expansion inland to the Hudson Valley down through
eastern PA. Current probs off the latest ensembles and National
Blend indicate a large zone of 50-80% probs for >1" across the
aforementioned area above with deterministic outputs closer to
2-2.5" into parts of Southern New England. MRGL risk inherited
remains in effect, but there's potential here for an upgrade as we
move closer to the D4 window, but want to see more of the CAMs to
make that decision.

Across the Southern U.S., heavy precipitation will preclude another
round of convection forming along a quasi-stationary front draped
from the Southern High Plains to the Southeastern CONUS. Probs for

1" are highest in-of the areas of Eastern OK into the Lower

Mississippi and southwestern Tennessee Valleys. Elevated theta_E's
and PWAT anomalies +2 dev. or greater indicate a formidable
environment capable of continued heavy rain potential that will
likely produce rainfall of 2-4", at least in some of the
thunderstorm activity that develops. The focal point along the
front will likely be where the heaviest rain will occur, or at
least be a low-level convergence mechanism that can enhance
regional convection. There's high enough confidence in the location
of convection for the D4 period to overlap with areas that will
have seen several inches the periods prior which led to an upgrade
to a SLGT risk positioned over portions of the Southern Plains
through parts of the Lower Mississippi and neighboring Tennessee
Valleys. The risk extends through the Smokey Mountains up into
parts of the Central Appalachians in eastern KY up into WV as the
convergence regime follows the frontal positioning over these
areas.

Day 5 is a transition period into a more typical summer time regime
for the CONUS with a longwave trough over the Northern U.S. and a
dome of mid and upper ridging positioning itself across the
Southwest. This will cause a persistent northwesterly flow pattern
across the Central and Southern High Plains over into the Lower
Mississippi Valley as progressive shortwave pulses eject out of the
Rockies and ride the prevailing northwesteries in place between the
ridge and trough. This highlights potential for MCS development and
flash flooding scenarios from the Front Range and points southeast
as the steering flow orients between the base of the trough and the northeastern flank of the ridge. This is historically projecting a
case of thunderstorm maturation and upscale growth over the area
between CO/KS down through OK/TX with potentially the Red River
Basin as a focus for thunderstorm activity. Eventually this ends up
migrating into the ArkLaTex and/or Lower Mississippi area which is
showing up in the QPF footprint on ensembles. With this becoming a
more stable signal in the global ensembles and aligning with the
NBM QPF output, a MRGL risk was added to the new D5 to account for
this potential evolution.

Kleebauer
=20

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!8WHSF9G_oyB4vd_XlR7OeC-8_3onJrnp3NRuSOW6PeSD= raC5XrjdRCKMSxgWHaNZ0aii37r6wm9sBjOQuxnrYKc2n4E$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!8WHSF9G_oyB4vd_XlR7OeC-8_3onJrnp3NRuSOW6PeSD= raC5XrjdRCKMSxgWHaNZ0aii37r6wm9sBjOQuxnr5pALH3A$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!8WHSF9G_oyB4vd_XlR7OeC-8_3onJrnp3NRuSOW6PeSD= raC5XrjdRCKMSxgWHaNZ0aii37r6wm9sBjOQuxnrY1Th2bY$=20



$$

=3D =3D =3D
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FOUS30 KWBC 192004
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
404 PM EDT Fri Jun 19 2026

Day 1
Valid 16Z Fri Jun 19 2026 - 12Z Sat Jun 20 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL IN EFFECT FOR
PORTIONS OF THE CENTRAL GULF COAST REGION...

...16Z Update...

No major changes were needed for the risk areas with this update.
Much of the expected rainfall is ongoing in the defined risk areas
across Texas, and for the MDT risk region, more widespread
scattered convection is expected to develop over the next few hours
with daytime heating. The convection appears unlikely to become
very organized, instead favoring pulse thunderstorms or small
clusters. Cell mergers appear to be the biggest threat when it
comes to localized renewed flash flooding this afternoon in the
Moderate Risk area across southern Alabama and Mississippi.

Elsewhere, a higher-end Slight has been issued for northern
Louisiana into northeast Texas for the ongoing very slow-moving
storms that are approaching Texarkana. These storms are expected to
continue building eastward into the afternoon, followed by a break
in the area for much of the overnight. Additional convection could
develop in the early morning hours.

The Slight over Georgia was expanded to near the coast for the
ongoing training storms in that area, which could persist into the
afternoon.

Finally, the Marginal Risk across the eastern Carolinas was dropped
with this update as the rain ongoing there pushes offshore and much
drier air replaces them, ending even a Marginal flooding threat
there.

Wegman

...Previous Discussion...

...Central Gulf Coast States...

Lingering flood impacts following the deluge over the last 24
hours will be exacerbated by additional rounds of slow-moving
convection today from central MS and eastern LA to the FL Panhandle
and far southwest GA. Low-to-mid level convergence will extend in
a west-east orientation just to the north of the Gulf Coast and
remain a focus for broken areas of showers and thunderstorms
throughout the day. These storms will tap into PWs above 2" and
remain relatively slow-moving with westerly convergent 850mb flow
less than 15 kts, leading to hourly rates of 2-3"/hr. Activity will
likely be ongoing across the region at 12z and pulse throughout
the day and into the overnight period. 00z HREF probabilities for
at least 3" per 6-hrs start the day 1 period as high as 60% across
southern AL and the FL Panhandle before becoming more scattered in
nature and lowering to around 30% for the overnight period. The
primary factor for maintaining the MDT risk is the fact that these
storms are likely to overlap with an area that recently received
widespread 4-8" rainfall totals (locally over 12") and soils are
easily overcome when rainfall rates exceed 2"/hr. This will lead to
additional scattered flash flood concerns on top of ongoing flood
impacts and recovery efforts.

...Southern Plains to the Upper Texas Coast...

Scattered flash flooding is also a concern from southern OK into
much of central and eastern TX today as thunderstorm activity
begins early this morning and gradually meanders east with time
through tonight. Vast amounts of uncertainty exist with the
mesoscale details surrounding the excessive rainfall forecast in
this area, particularly for being a day 1 forecast, but PWs
near/slightly above 2" and widespread dew points into the upper 70s
and low 80s point to an environment ripe for intense rainfall
rates. As convection develops early this morning the expectation is
for an MCV or multiple MCVs to spawn ahead of an approaching weak
shortwave and within a building ridge over the south-central U.S..
This weak steering pattern will lead to conditions where MCV
location and outflow boundaries could drive the convective mode.
Even if thunderstorms remain mostly progressive after cold pools
develop, intense rainfall rates of 2-3" are possible throughout the
Southern Plains into eastern TX and the ArkLaTex. One area of
focus to monitor into the overnight period into Saturday morning
will be across eastern TX into central LA where a frontal boundary
is forecast to drape and potential interact with a weak surface
low or remnant MCV. Several CAMs indicate more widespread
thunderstorm activity around 12z Sat. here or just to the south
across southeast TX as the nocturnal low-level flow increases
towards the frontal boundary. 00z HREF neighborhood probs for at
least 3" per 6-hrs are generally around 30% here, but REFS probs
are much higher (60%) and farther south along the upper TX
coastline. Thus, a large SLGT risk is in effect for this region to
highlight the widely scattered/uncertain nature of thunderstorms,
but while also likely containing intense rainfall rates capable of
flash flood impacts.

Snell
=20

Day 2
Valid 12Z Sat Jun 20 2026 - 12Z Sun Jun 21 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE CENTRAL PLAINS AND MISSOURI VALLEY...

...2030Z Update...

Few changes were needed for the Saturday/Day 2 period. Expected
rainfall over the Central Plains Moderate Risk area remains very
similar to the previous forecast. Despite heavy rains in the area
in recent weeks, soils in the area have have some time to dry out,
which should work to mitigate some of the flooding impacts in the
area. Regardless, in much of the Moderate Risk area, enough rain is
expected from the overnight MCS to result in scattered to numerous
instances of flash flooding where the heaviest rains persist the
longest. This will roughly follow the eastern 2/3 of the NE/KS
border. Expected rainfall amounts have come down a bit towards far
eastern Kansas into Missouri, likely due to a bit faster forward
speed of the MCS's associated storms by the time the MCS reaches
that area after midnight Sunday morning, so the Moderate Risk was
trimmed and the Slight in western Missouri was trimmed as well.

Along the Gulf Coast, few changes were needed. As with today,
slow-moving training convection in the Slight Risk area is likely
to impact many areas of yesterday's High Risk and today's Moderate
Risk areas. Sufficient dry time in between should prevent the
widespread impacts that would necessitate a Moderate Risk upgrade
in this area for now...but the area will certainly need to continue
to be monitored to ensure that expected behavior persists.

Wegman

...Central Plains and Missouri Valley...

A large area of heavy rain associated with a developing MCS
starting Saturday afternoon and continuing into Saturday night is
expected to bring widespread heavy rainfall across portions of the
central Plains into the Missouri Valley with the greatest threat
currently expected across southeastern Nebraska, northeastern
Kansas, and far northwestern Missouri/southwestern Iowa. Storms
are expected to initiate Saturday afternoon with peak heating over
the central High Plains and ahead of a racing shortwave crossing
the Rockies. Meanwhile, a LLJ of southeasterly flow will pump deep
Gulf moisture up the Plains through the day. This will force the
dryline to race eastward in response. The warm front associated
with the low and the dry line will uplift the deep moisture,
resulting in widespread shower and thunderstorm development. These
storms are expected to grow upscale into an expansive, organized
convective system into the evening and overnight hours that will
then track southeasterly across the risk area.

The latest deterministic guidance shows areal average rainfall
totals along the expected path of the MCS in the 2-3" range with
locally higher amounts of 4-6", more than sufficient to lead to
scattered and potentially widespread flash flooding, which has
prompted the level 3/4 Moderate Risk. As is usually the case with
convective systems the exact path and duration will be determined
by more mesoscale details than the guidance can typically pin down
at this time frame, so some areal modification and possible
expansion of the Moderate Risk will be likely over the next couple
of days. The most likely area for expansion would be further to
southeast into more of western Missouri and east-
central/southeastern Kansas. However, given the noted uncertainty
with the evolution of these types of systems at this timeframe,
have limited the extent of the risk area to also overlap where the
greatest support/confidence is shown by the ensemble
mean/probabilistic guidance.

...Eastern Texas through the Central Gulf Coast...

One more day of scattered slow-moving storms is expected on
Saturday across the Deep South between eastern TX and southern
AL/FL Panhandle. The lingering frontal boundary draped north of the
Gulf Coast will begin to lift north during the day and leave
convection widely scattered, but more focused activity is likely
during the morning hours as high pressure over the Tennessee Valley
keeps the thermal/moisture gradient rather sharp and focuses
ongoing thunderstorm activity within PWs above 2". Lingering MCV(s)
from the day 1 period across eastern TX and the Lower Mississippi
Valley could also add locations for more organized thunderstorm
activity. The soils in this region also remain extremely saturated
and sensitive to additional intense rainfall rates, leading to the
potential for scattered instances of flash flooding on Saturday and
the SLGT risk of excessive rainfall.

Snell
=20

Day 3
Valid 12Z Sun Jun 21 2026 - 12Z Mon Jun 22 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM EASTERN
OKLAHOMA AND THE OZARKS THROUGH MUCH OF THE MIDWEST AND OHIO
VALLEY AS WELL AS FOR PORTIONS OF SOUTH DAKOTA...

...2030Z Update...

Across the center of the country from the Ozarks to the Midwest,
few changes were needed with this update. The MCS from the Plains
on D2 continues east across the Midwest on D3/Sunday. As it moves
east, it encounters increasingly plentiful Gulf moisture already in
place, while the low and the MCS itself draw additional moisture
advection from the south into the system. This will ensure the
storms continue right through the period, as the MCS slowly moves
east. As usual, the southern end of the MCS appears to be the area
of greatest concern, as the storms on the south side are the first
to ingest the deep Gulf moisture over the area. This will encourage
the storms to linger and backbuild to the southwest, extending the
duration of the heavy rainfall in those areas. Further, FFGs across
much of the Midwest remain depressed due to recent heavy rainfall,
and soils are wetter than normal. Some drying in between now and
Sunday should help to mitigate flooding somewhat, but the strongest
storms should have no trouble exceeding the FFGs as 2-3 inch/hour
rates are expected. A Moderate Risk remains possible. If one were
to be issued, it appears a band extending west to east along I-70
in Missouri, then following I-64 across southern Illinois, Indiana,
and then east through Cincinnati and northern Kentucky appears most
probable. However, the details of the storms and their placement
remain difficult to pinpoint, especially as this remains outside of
the CAMs range, so additional changes are likely.

...South Dakota...

An MCS, separate from the one going into the Midwest, likely gets
started across South Dakota Saturday night. With dry soils in the
area, the rain with the intial storms then are likely to be
absorbed with only isolated flooding concerns. However, going into
Sunday morning, the redevelopment of the storms across the area
will increase the flooding potential in the area with time. A
southeasterly jet of moisture wrapping around a low over Nebraska
should keep a continuous supply of moisture heading into the
storms, and with that windflow working counter to the southeasterly
movement of the storms, that should work to slow the storms'
forward speed, worsening flooding concerns. Given all this and in
coordination with ABR/Aberdeen, SD and UNR/Rapid City, SD forecast
offices, a Slight Risk area was introduced with this update.

Wegman

...Previous Discussion...

...Midwest...

By the start of the day 3 forecast period a potent shortwave and
related surface low are expected to eject eastward out of the
central Plains into the Midwest. There remains some uncertainty
regarding the speed and latitude of these features, but PWs above
the 90th climatological percentile (per the 00z GEFS) overlapping
with soils likely still recovering from recent heavy rain in the
Midwest will lead to at least scattered flash flooding concerns.
NBM probabilities for at least 2" are very high (between 60-80%)
and cover much of the northern SLGT risk area from MO/IA to OH.
Locally higher totals are likely given the convective environment.
The progressive nature of these storms may end up limiting the
severity of flash flood impacts, but a MDT risk upgrade is possible
should training/back- building elements become more obvious in the
short range updates, particularly along the leading warm front
ahead of the primary surface low.

...Southern Plains, Ozarks, and Lower Ohio Valley...

The setup on Sunday could lead to a southern secondary axis of
heaviest QPF and flash flooding impacts. The southern end of the
Saturday night thunderstorm complex/MCS is likely to sink
southeastward near a trailing cold front and impact areas near the
Ozarks early Sunday. Then, the expectation is for reforming
scattered convection during peak daytime heating and reorganization
of thunderstorms overnight Sunday associated with the LLJ to span
from OK to the Lower Ohio Valley, including northern AR, southern
MO, and western TN/KY. This combines for guidance to currently
depict current QPF amounts of 2-4" and an average localized max of
6". There remains obvious mesoscale uncertainties at this stage,
but with Pws near the 90th climatological percentile and a
favorably oriented west- east frontal boundary, it's possible a MDT
risk upgrade may be needed once CAMs come into forecast range. For
the Lower Ohio Valley in particular, some guidance also highlights thunderstorms associated with the initial warm front lifting
northward, which could add yet another potential for slow-moving
repeating thunderstorms.

Snell
=20

Day 4 and Day 5

Valid 12Z Mon Jun 22 2026 - 12Z Wed Jun 24 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM PORTIONS OF
THE SOUTHERN PLAINS, LOWER MISSISSIPPI AND TENNESSEE VALLEYS, AND
CENTRAL APPALACHIANS ON DAY 4...

Day 4 continues to an active pattern through a good portion of the
CONUS, east of the Mississippi with a progressive trough axis
pushing through the Great Lakes and Northeast leading to periods of
moderate to heavy rainfall from the Ohio Valley into the Mid
Atlantic and Northeast. Areas of the Northeast are subject to
thunderstorm prospects with the best chance for flash flooding
likely to occur in the urban footprint from Philadelphia up to
Boston with an expansion inland to the Hudson Valley down through
eastern PA. Current probs off the latest ensembles and National
Blend indicate a large zone of 50-80% probs for >1" across the
aforementioned area above with deterministic outputs closer to
2-2.5" into parts of Southern New England. MRGL risk inherited
remains in effect, but there's potential here for an upgrade as we
move closer to the D4 window, but want to see more of the CAMs to
make that decision.

Across the Southern U.S., heavy precipitation will preclude another
round of convection forming along a quasi-stationary front draped
from the Southern High Plains to the Southeastern CONUS. Probs for

1" are highest in-of the areas of Eastern OK into the Lower

Mississippi and southwestern Tennessee Valleys. Elevated theta_E's
and PWAT anomalies +2 dev. or greater indicate a formidable
environment capable of continued heavy rain potential that will
likely produce rainfall of 2-4", at least in some of the
thunderstorm activity that develops. The focal point along the
front will likely be where the heaviest rain will occur, or at
least be a low-level convergence mechanism that can enhance
regional convection. There's high enough confidence in the location
of convection for the D4 period to overlap with areas that will
have seen several inches the periods prior which led to an upgrade
to a SLGT risk positioned over portions of the Southern Plains
through parts of the Lower Mississippi and neighboring Tennessee
Valleys. The risk extends through the Smokey Mountains up into
parts of the Central Appalachians in eastern KY up into WV as the
convergence regime follows the frontal positioning over these
areas.

Day 5 is a transition period into a more typical summer time regime
for the CONUS with a longwave trough over the Northern U.S. and a
dome of mid and upper ridging positioning itself across the
Southwest. This will cause a persistent northwesterly flow pattern
across the Central and Southern High Plains over into the Lower
Mississippi Valley as progressive shortwave pulses eject out of the
Rockies and ride the prevailing northwesteries in place between the
ridge and trough. This highlights potential for MCS development and
flash flooding scenarios from the Front Range and points southeast
as the steering flow orients between the base of the trough and the northeastern flank of the ridge. This is historically projecting a
case of thunderstorm maturation and upscale growth over the area
between CO/KS down through OK/TX with potentially the Red River
Basin as a focus for thunderstorm activity. Eventually this ends up
migrating into the ArkLaTex and/or Lower Mississippi area which is
showing up in the QPF footprint on ensembles. With this becoming a
more stable signal in the global ensembles and aligning with the
NBM QPF output, a MRGL risk was added to the new D5 to account for
this potential evolution.

Kleebauer
=20

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!8y4Ri2YfWPRr6ubfE8wy47xNi4x7rwGVvrl_JbB0zPpP= _0QOdPMK3lSX0IBcJVRPN1_ST2q93lNbCBhE82gz8zcU45M$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!8y4Ri2YfWPRr6ubfE8wy47xNi4x7rwGVvrl_JbB0zPpP= _0QOdPMK3lSX0IBcJVRPN1_ST2q93lNbCBhE82gzfwWfhe8$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!8y4Ri2YfWPRr6ubfE8wy47xNi4x7rwGVvrl_JbB0zPpP= _0QOdPMK3lSX0IBcJVRPN1_ST2q93lNbCBhE82gzS3LjL9Q$=20



$$

=3D =3D =3D
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--- SBBSecho 3.28-Linux
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FOUS30 KWBC 192013
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
413 PM EDT Fri Jun 19 2026

Day 1
Valid 16Z Fri Jun 19 2026 - 12Z Sat Jun 20 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL IN EFFECT FOR
PORTIONS OF THE CENTRAL GULF COAST REGION...

...16Z Update...

No major changes were needed for the risk areas with this update.
Much of the expected rainfall is ongoing in the defined risk areas
across Texas, and for the MDT risk region, more widespread
scattered convection is expected to develop over the next few hours
with daytime heating. The convection appears unlikely to become
very organized, instead favoring pulse thunderstorms or small
clusters. Cell mergers appear to be the biggest threat when it
comes to localized renewed flash flooding this afternoon in the
Moderate Risk area across southern Alabama and Mississippi.

Elsewhere, a higher-end Slight has been issued for northern
Louisiana into northeast Texas for the ongoing very slow-moving
storms that are approaching Texarkana. These storms are expected to
continue building eastward into the afternoon, followed by a break
in the area for much of the overnight. Additional convection could
develop in the early morning hours.

The Slight over Georgia was expanded to near the coast for the
ongoing training storms in that area, which could persist into the
afternoon.

Finally, the Marginal Risk across the eastern Carolinas was dropped
with this update as the rain ongoing there pushes offshore and much
drier air replaces them, ending even a Marginal flooding threat
there.

Wegman

...Previous Discussion...

...Central Gulf Coast States...

Lingering flood impacts following the deluge over the last 24
hours will be exacerbated by additional rounds of slow-moving
convection today from central MS and eastern LA to the FL Panhandle
and far southwest GA. Low-to-mid level convergence will extend in
a west-east orientation just to the north of the Gulf Coast and
remain a focus for broken areas of showers and thunderstorms
throughout the day. These storms will tap into PWs above 2" and
remain relatively slow-moving with westerly convergent 850mb flow
less than 15 kts, leading to hourly rates of 2-3"/hr. Activity will
likely be ongoing across the region at 12z and pulse throughout
the day and into the overnight period. 00z HREF probabilities for
at least 3" per 6-hrs start the day 1 period as high as 60% across
southern AL and the FL Panhandle before becoming more scattered in
nature and lowering to around 30% for the overnight period. The
primary factor for maintaining the MDT risk is the fact that these
storms are likely to overlap with an area that recently received
widespread 4-8" rainfall totals (locally over 12") and soils are
easily overcome when rainfall rates exceed 2"/hr. This will lead to
additional scattered flash flood concerns on top of ongoing flood
impacts and recovery efforts.

...Southern Plains to the Upper Texas Coast...

Scattered flash flooding is also a concern from southern OK into
much of central and eastern TX today as thunderstorm activity
begins early this morning and gradually meanders east with time
through tonight. Vast amounts of uncertainty exist with the
mesoscale details surrounding the excessive rainfall forecast in
this area, particularly for being a day 1 forecast, but PWs
near/slightly above 2" and widespread dew points into the upper 70s
and low 80s point to an environment ripe for intense rainfall
rates. As convection develops early this morning the expectation is
for an MCV or multiple MCVs to spawn ahead of an approaching weak
shortwave and within a building ridge over the south-central U.S..
This weak steering pattern will lead to conditions where MCV
location and outflow boundaries could drive the convective mode.
Even if thunderstorms remain mostly progressive after cold pools
develop, intense rainfall rates of 2-3" are possible throughout the
Southern Plains into eastern TX and the ArkLaTex. One area of
focus to monitor into the overnight period into Saturday morning
will be across eastern TX into central LA where a frontal boundary
is forecast to drape and potential interact with a weak surface
low or remnant MCV. Several CAMs indicate more widespread
thunderstorm activity around 12z Sat. here or just to the south
across southeast TX as the nocturnal low-level flow increases
towards the frontal boundary. 00z HREF neighborhood probs for at
least 3" per 6-hrs are generally around 30% here, but REFS probs
are much higher (60%) and farther south along the upper TX
coastline. Thus, a large SLGT risk is in effect for this region to
highlight the widely scattered/uncertain nature of thunderstorms,
but while also likely containing intense rainfall rates capable of
flash flood impacts.

Snell
=20

Day 2
Valid 12Z Sat Jun 20 2026 - 12Z Sun Jun 21 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE CENTRAL PLAINS AND MISSOURI VALLEY...

...2030Z Update...

Few changes were needed for the Saturday/Day 2 period. Expected
rainfall over the Central Plains Moderate Risk area remains very
similar to the previous forecast. Despite heavy rains in the area
in recent weeks, soils in the area have have some time to dry out,
which should work to mitigate some of the flooding impacts in the
area. Regardless, in much of the Moderate Risk area, enough rain is
expected from the overnight MCS to result in scattered to numerous
instances of flash flooding where the heaviest rains persist the
longest. This will roughly follow the eastern 2/3 of the NE/KS
border. Expected rainfall amounts have come down a bit towards far
eastern Kansas into Missouri, likely due to a bit faster forward
speed of the MCS's associated storms by the time the MCS reaches
that area after midnight Sunday morning, so the Moderate Risk was
trimmed and the Slight in western Missouri was trimmed as well.

Along the Gulf Coast, few changes were needed. As with today,
slow-moving training convection in the Slight Risk area is likely
to impact many areas of yesterday's High Risk and today's Moderate
Risk areas. Sufficient dry time in between should prevent the
widespread impacts that would necessitate a Moderate Risk upgrade
in this area for now...but the area will certainly need to continue
to be monitored to ensure that expected behavior persists.

Wegman

...Central Plains and Missouri Valley...

A large area of heavy rain associated with a developing MCS
starting Saturday afternoon and continuing into Saturday night is
expected to bring widespread heavy rainfall across portions of the
central Plains into the Missouri Valley with the greatest threat
currently expected across southeastern Nebraska, northeastern
Kansas, and far northwestern Missouri/southwestern Iowa. Storms
are expected to initiate Saturday afternoon with peak heating over
the central High Plains and ahead of a racing shortwave crossing
the Rockies. Meanwhile, a LLJ of southeasterly flow will pump deep
Gulf moisture up the Plains through the day. This will force the
dryline to race eastward in response. The warm front associated
with the low and the dry line will uplift the deep moisture,
resulting in widespread shower and thunderstorm development. These
storms are expected to grow upscale into an expansive, organized
convective system into the evening and overnight hours that will
then track southeasterly across the risk area.

The latest deterministic guidance shows areal average rainfall
totals along the expected path of the MCS in the 2-3" range with
locally higher amounts of 4-6", more than sufficient to lead to
scattered and potentially widespread flash flooding, which has
prompted the level 3/4 Moderate Risk. As is usually the case with
convective systems the exact path and duration will be determined
by more mesoscale details than the guidance can typically pin down
at this time frame, so some areal modification and possible
expansion of the Moderate Risk will be likely over the next couple
of days. The most likely area for expansion would be further to
southeast into more of western Missouri and east-
central/southeastern Kansas. However, given the noted uncertainty
with the evolution of these types of systems at this timeframe,
have limited the extent of the risk area to also overlap where the
greatest support/confidence is shown by the ensemble
mean/probabilistic guidance.

...Eastern Texas through the Central Gulf Coast...

One more day of scattered slow-moving storms is expected on
Saturday across the Deep South between eastern TX and southern
AL/FL Panhandle. The lingering frontal boundary draped north of the
Gulf Coast will begin to lift north during the day and leave
convection widely scattered, but more focused activity is likely
during the morning hours as high pressure over the Tennessee Valley
keeps the thermal/moisture gradient rather sharp and focuses
ongoing thunderstorm activity within PWs above 2". Lingering MCV(s)
from the day 1 period across eastern TX and the Lower Mississippi
Valley could also add locations for more organized thunderstorm
activity. The soils in this region also remain extremely saturated
and sensitive to additional intense rainfall rates, leading to the
potential for scattered instances of flash flooding on Saturday and
the SLGT risk of excessive rainfall.

Snell
=20

Day 3
Valid 12Z Sun Jun 21 2026 - 12Z Mon Jun 22 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM EASTERN
OKLAHOMA AND THE OZARKS THROUGH MUCH OF THE MIDWEST AND OHIO
VALLEY AS WELL AS FOR PORTIONS OF SOUTH DAKOTA...

...2030Z Update...

Across the center of the country from the Ozarks to the Midwest,
few changes were needed with this update. The MCS from the Plains
on D2 continues east across the Midwest on D3/Sunday. As it moves
east, it encounters increasingly plentiful Gulf moisture already in
place, while the low and the MCS itself draw additional moisture
advection from the south into the system. This will ensure the
storms continue right through the period, as the MCS slowly moves
east. As usual, the southern end of the MCS appears to be the area
of greatest concern, as the storms on the south side are the first
to ingest the deep Gulf moisture over the area. This will encourage
the storms to linger and backbuild to the southwest, extending the
duration of the heavy rainfall in those areas. Further, FFGs across
much of the Midwest remain depressed due to recent heavy rainfall,
and soils are wetter than normal. Some drying in between now and
Sunday should help to mitigate flooding somewhat, but the strongest
storms should have no trouble exceeding the FFGs as 2-3 inch/hour
rates are expected. A Moderate Risk remains possible. If one were
to be issued, it appears a band extending west to east along I-70
in Missouri, then following I-64 across southern Illinois, Indiana,
and then east through Cincinnati and northern Kentucky appears most
probable. However, the details of the storms and their placement
remain difficult to pinpoint, especially as this remains outside of
the CAMs range, so additional changes are likely.

...South Dakota...

An MCS, separate from the one going into the Midwest, likely gets
started across South Dakota Saturday night. With dry soils in the
area, the rain with the intial storms then are likely to be
absorbed with only isolated flooding concerns. However, going into
Sunday morning, the redevelopment of the storms across the area
will increase the flooding potential in the area with time. A
southeasterly jet of moisture wrapping around a low over Nebraska
should keep a continuous supply of moisture heading into the
storms, and with that windflow working counter to the southeasterly
movement of the storms, that should work to slow the storms'
forward speed, worsening flooding concerns. Given all this and in
coordination with ABR/Aberdeen, SD and UNR/Rapid City, SD forecast
offices, a Slight Risk area was introduced with this update.

Wegman

...Previous Discussion...

...Midwest...

By the start of the day 3 forecast period a potent shortwave and
related surface low are expected to eject eastward out of the
central Plains into the Midwest. There remains some uncertainty
regarding the speed and latitude of these features, but PWs above
the 90th climatological percentile (per the 00z GEFS) overlapping
with soils likely still recovering from recent heavy rain in the
Midwest will lead to at least scattered flash flooding concerns.
NBM probabilities for at least 2" are very high (between 60-80%)
and cover much of the northern SLGT risk area from MO/IA to OH.
Locally higher totals are likely given the convective environment.
The progressive nature of these storms may end up limiting the
severity of flash flood impacts, but a MDT risk upgrade is possible
should training/back- building elements become more obvious in the
short range updates, particularly along the leading warm front
ahead of the primary surface low.

...Southern Plains, Ozarks, and Lower Ohio Valley...

The setup on Sunday could lead to a southern secondary axis of
heaviest QPF and flash flooding impacts. The southern end of the
Saturday night thunderstorm complex/MCS is likely to sink
southeastward near a trailing cold front and impact areas near the
Ozarks early Sunday. Then, the expectation is for reforming
scattered convection during peak daytime heating and reorganization
of thunderstorms overnight Sunday associated with the LLJ to span
from OK to the Lower Ohio Valley, including northern AR, southern
MO, and western TN/KY. This combines for guidance to currently
depict current QPF amounts of 2-4" and an average localized max of
6". There remains obvious mesoscale uncertainties at this stage,
but with Pws near the 90th climatological percentile and a
favorably oriented west- east frontal boundary, it's possible a MDT
risk upgrade may be needed once CAMs come into forecast range. For
the Lower Ohio Valley in particular, some guidance also highlights thunderstorms associated with the initial warm front lifting
northward, which could add yet another potential for slow-moving
repeating thunderstorms.

Snell
=20

Day 4 and Day 5

Valid 12Z Mon Jun 22 2026 - 12Z Wed Jun 24 2026
...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM PORTIONS OF
THE SOUTHERN PLAINS, LOWER MISSISSIPPI AND TENNESSEE VALLEYS, AND
CENTRAL APPALACHIANS ON DAY 4...

2030Z Update...
Ensemble and deterministic runs from the dayshift largely supported
the previously-issued excessive rainfall outlook and discussion.
Changes were minimnal and continued to focus in the same area.

Bann

Previous Discussion...
Day 4 continues to an active pattern through a good portion of the
CONUS, east of the Mississippi with a progressive trough axis
pushing through the Great Lakes and Northeast leading to periods of
moderate to heavy rainfall from the Ohio Valley into the Mid
Atlantic and Northeast. Areas of the Northeast are subject to
thunderstorm prospects with the best chance for flash flooding
likely to occur in the urban footprint from Philadelphia up to
Boston with an expansion inland to the Hudson Valley down through
eastern PA. Current probs off the latest ensembles and National
Blend indicate a large zone of 50-80% probs for >1" across the
aforementioned area above with deterministic outputs closer to
2-2.5" into parts of Southern New England. MRGL risk inherited
remains in effect, but there's potential here for an upgrade as we
move closer to the D4 window, but want to see more of the CAMs to
make that decision.

Across the Southern U.S., heavy precipitation will preclude another
round of convection forming along a quasi-stationary front draped
from the Southern High Plains to the Southeastern CONUS. Probs for

1" are highest in-of the areas of Eastern OK into the Lower

Mississippi and southwestern Tennessee Valleys. Elevated theta_E's
and PWAT anomalies +2 dev. or greater indicate a formidable
environment capable of continued heavy rain potential that will
likely produce rainfall of 2-4", at least in some of the
thunderstorm activity that develops. The focal point along the
front will likely be where the heaviest rain will occur, or at
least be a low-level convergence mechanism that can enhance
regional convection. There's high enough confidence in the location
of convection for the D4 period to overlap with areas that will
have seen several inches the periods prior which led to an upgrade
to a SLGT risk positioned over portions of the Southern Plains
through parts of the Lower Mississippi and neighboring Tennessee
Valleys. The risk extends through the Smokey Mountains up into
parts of the Central Appalachians in eastern KY up into WV as the
convergence regime follows the frontal positioning over these
areas.

Day 5 is a transition period into a more typical summer time regime
for the CONUS with a longwave trough over the Northern U.S. and a
dome of mid and upper ridging positioning itself across the
Southwest. This will cause a persistent northwesterly flow pattern
across the Central and Southern High Plains over into the Lower
Mississippi Valley as progressive shortwave pulses eject out of the
Rockies and ride the prevailing northwesteries in place between the
ridge and trough. This highlights potential for MCS development and
flash flooding scenarios from the Front Range and points southeast
as the steering flow orients between the base of the trough and the northeastern flank of the ridge. This is historically projecting a
case of thunderstorm maturation and upscale growth over the area
between CO/KS down through OK/TX with potentially the Red River
Basin as a focus for thunderstorm activity. Eventually this ends up
migrating into the ArkLaTex and/or Lower Mississippi area which is
showing up in the QPF footprint on ensembles. With this becoming a
more stable signal in the global ensembles and aligning with the
NBM QPF output, a MRGL risk was added to the new D5 to account for
this potential evolution.

Kleebauer
=20

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!_phWTZONTF-7cpapW2EtSYgsAfTtnJz-eAWFo9-IHE1G= Q4kjtYTFI0s0iZzI8mK6xRPdnSBS_9E_iH_rpW-YpxkwX10$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!_phWTZONTF-7cpapW2EtSYgsAfTtnJz-eAWFo9-IHE1G= Q4kjtYTFI0s0iZzI8mK6xRPdnSBS_9E_iH_rpW-Y0XxvBtk$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!_phWTZONTF-7cpapW2EtSYgsAfTtnJz-eAWFo9-IHE1G= Q4kjtYTFI0s0iZzI8mK6xRPdnSBS_9E_iH_rpW-YoF4l_S4$=20



$$

=3D =3D =3D
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FOUS30 KWBC 200057
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
857 PM EDT Fri Jun 19 2026

Day 1
Valid 01Z Sat Jun 20 2026 - 12Z Sat Jun 20 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL IN EFFECT FOR
PORTIONS OF THE CENTRAL GULF COAST REGION...

...01Z Update...
Some redrawing of the boundaries of various categories was done to
fit latest trends in imagery/obs and models,...but the primary
focus for heavy to excessive rainfall continues to be along/near
the gulf coast overnight. Guidance has not been doing particularly
well in handling the convection so tended to leave the Moderate in place...especially where convection was still active in
Louisiana and Mississippi (reference MPD 472). To the
east...trimmed areas out of the higher-ERO categories where a
well-defined outflow has been making its way southward across the
peninsula and the northern Gulf. There was a northward expansion of
the Slight Risk area across northern Mississippi and northern
Alabama due to on-going convection (reference MPD 0471. The
expectation here is that the convection should be tapering off but
that it remained a potential source for additional heavy rain in
the short term (reference MPD 0471). Convection moving across the
international border into portions of South Texas will encounter an
atmosphere with deeper moisture...which would support heavier
rainfall rates and may lead to isolated pr widely scattered
instances of flash flooding.

Bann

...16Z Update...
No major changes were needed for the risk areas with this update.
Much of the expected rainfall is ongoing in the defined risk areas
across Texas, and for the MDT risk region, more widespread
scattered convection is expected to develop over the next few hours
with daytime heating. The convection appears unlikely to become
very organized, instead favoring pulse thunderstorms or small
clusters. Cell mergers appear to be the biggest threat when it
comes to localized renewed flash flooding this afternoon in the
Moderate Risk area across southern Alabama and Mississippi.
Elsewhere, a higher-end Slight has been issued for northern
Louisiana into northeast Texas for the ongoing very slow-moving
storms that are approaching Texarkana. These storms are expected to
continue building eastward into the afternoon, followed by a break
in the area for much of the overnight. Additional convection could
develop in the early morning hours.
The Slight over Georgia was expanded to near the coast for the
ongoing training storms in that area, which could persist into the
afternoon.

Finally, the Marginal Risk across the eastern Carolinas was dropped
with this update as the rain ongoing there pushes offshore and much
drier air replaces them, ending even a Marginal flooding threat
there.

Wegman

...Previous Discussion...

...Central Gulf Coast States...

Lingering flood impacts following the deluge over the last 24
hours will be exacerbated by additional rounds of slow-moving
convection today from central MS and eastern LA to the FL Panhandle
and far southwest GA. Low-to-mid level convergence will extend in
a west-east orientation just to the north of the Gulf Coast and
remain a focus for broken areas of showers and thunderstorms
throughout the day. These storms will tap into PWs above 2" and
remain relatively slow-moving with westerly convergent 850mb flow
less than 15 kts, leading to hourly rates of 2-3"/hr. Activity will
likely be ongoing across the region at 12z and pulse throughout
the day and into the overnight period. 00z HREF probabilities for
at least 3" per 6-hrs start the day 1 period as high as 60% across
southern AL and the FL Panhandle before becoming more scattered in
nature and lowering to around 30% for the overnight period. The
primary factor for maintaining the MDT risk is the fact that these
storms are likely to overlap with an area that recently received
widespread 4-8" rainfall totals (locally over 12") and soils are
easily overcome when rainfall rates exceed 2"/hr. This will lead to
additional scattered flash flood concerns on top of ongoing flood
impacts and recovery efforts.

...Southern Plains to the Upper Texas Coast...
Scattered flash flooding is also a concern from southern OK into
much of central and eastern TX today as thunderstorm activity
begins early this morning and gradually meanders east with time
through tonight. Vast amounts of uncertainty exist with the
mesoscale details surrounding the excessive rainfall forecast in
this area, particularly for being a day 1 forecast, but PWs
near/slightly above 2" and widespread dew points into the upper 70s
and low 80s point to an environment ripe for intense rainfall
rates. As convection develops early this morning the expectation is
for an MCV or multiple MCVs to spawn ahead of an approaching weak
shortwave and within a building ridge over the south-central U.S..
This weak steering pattern will lead to conditions where MCV
location and outflow boundaries could drive the convective mode.
Even if thunderstorms remain mostly progressive after cold pools
develop, intense rainfall rates of 2-3" are possible throughout the
Southern Plains into eastern TX and the ArkLaTex. One area of
focus to monitor into the overnight period into Saturday morning
will be across eastern TX into central LA where a frontal boundary
is forecast to drape and potential interact with a weak surface
low or remnant MCV. Several CAMs indicate more widespread
thunderstorm activity around 12z Sat. here or just to the south
across southeast TX as the nocturnal low-level flow increases
towards the frontal boundary. 00z HREF neighborhood probs for at
least 3" per 6-hrs are generally around 30% here, but REFS probs
are much higher (60%) and farther south along the upper TX
coastline. Thus, a large SLGT risk is in effect for this region to
highlight the widely scattered/uncertain nature of thunderstorms,
but while also likely containing intense rainfall rates capable of
flash flood impacts.

Snell
=20

Day 2
Valid 12Z Sat Jun 20 2026 - 12Z Sun Jun 21 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS
OF THE CENTRAL PLAINS AND MISSOURI VALLEY...

...2030Z Update...

Few changes were needed for the Saturday/Day 2 period. Expected
rainfall over the Central Plains Moderate Risk area remains very
similar to the previous forecast. Despite heavy rains in the area
in recent weeks, soils in the area have have some time to dry out,
which should work to mitigate some of the flooding impacts in the
area. Regardless, in much of the Moderate Risk area, enough rain is
expected from the overnight MCS to result in scattered to numerous
instances of flash flooding where the heaviest rains persist the
longest. This will roughly follow the eastern 2/3 of the NE/KS
border. Expected rainfall amounts have come down a bit towards far
eastern Kansas into Missouri, likely due to a bit faster forward
speed of the MCS's associated storms by the time the MCS reaches
that area after midnight Sunday morning, so the Moderate Risk was
trimmed and the Slight in western Missouri was trimmed as well.

Along the Gulf Coast, few changes were needed. As with today,
slow-moving training convection in the Slight Risk area is likely
to impact many areas of yesterday's High Risk and today's Moderate
Risk areas. Sufficient dry time in between should prevent the
widespread impacts that would necessitate a Moderate Risk upgrade
in this area for now...but the area will certainly need to continue
to be monitored to ensure that expected behavior persists.

Wegman

...Central Plains and Missouri Valley...

A large area of heavy rain associated with a developing MCS
starting Saturday afternoon and continuing into Saturday night is
expected to bring widespread heavy rainfall across portions of the
central Plains into the Missouri Valley with the greatest threat
currently expected across southeastern Nebraska, northeastern
Kansas, and far northwestern Missouri/southwestern Iowa. Storms
are expected to initiate Saturday afternoon with peak heating over
the central High Plains and ahead of a racing shortwave crossing
the Rockies. Meanwhile, a LLJ of southeasterly flow will pump deep
Gulf moisture up the Plains through the day. This will force the
dryline to race eastward in response. The warm front associated
with the low and the dry line will uplift the deep moisture,
resulting in widespread shower and thunderstorm development. These
storms are expected to grow upscale into an expansive, organized
convective system into the evening and overnight hours that will
then track southeasterly across the risk area.

The latest deterministic guidance shows areal average rainfall
totals along the expected path of the MCS in the 2-3" range with
locally higher amounts of 4-6", more than sufficient to lead to
scattered and potentially widespread flash flooding, which has
prompted the level 3/4 Moderate Risk. As is usually the case with
convective systems the exact path and duration will be determined
by more mesoscale details than the guidance can typically pin down
at this time frame, so some areal modification and possible
expansion of the Moderate Risk will be likely over the next couple
of days. The most likely area for expansion would be further to
southeast into more of western Missouri and east-
central/southeastern Kansas. However, given the noted uncertainty
with the evolution of these types of systems at this timeframe,
have limited the extent of the risk area to also overlap where the
greatest support/confidence is shown by the ensemble
mean/probabilistic guidance.

...Eastern Texas through the Central Gulf Coast...

One more day of scattered slow-moving storms is expected on
Saturday across the Deep South between eastern TX and southern
AL/FL Panhandle. The lingering frontal boundary draped north of the
Gulf Coast will begin to lift north during the day and leave
convection widely scattered, but more focused activity is likely
during the morning hours as high pressure over the Tennessee Valley
keeps the thermal/moisture gradient rather sharp and focuses
ongoing thunderstorm activity within PWs above 2". Lingering MCV(s)
from the day 1 period across eastern TX and the Lower Mississippi
Valley could also add locations for more organized thunderstorm
activity. The soils in this region also remain extremely saturated
and sensitive to additional intense rainfall rates, leading to the
potential for scattered instances of flash flooding on Saturday and
the SLGT risk of excessive rainfall.

Snell
=20

Day 3
Valid 12Z Sun Jun 21 2026 - 12Z Mon Jun 22 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM EASTERN
OKLAHOMA AND THE OZARKS THROUGH MUCH OF THE MIDWEST AND OHIO
VALLEY AS WELL AS FOR PORTIONS OF SOUTH DAKOTA...

...2030Z Update...

Across the center of the country from the Ozarks to the Midwest,
few changes were needed with this update. The MCS from the Plains
on D2 continues east across the Midwest on D3/Sunday. As it moves
east, it encounters increasingly plentiful Gulf moisture already in
place, while the low and the MCS itself draw additional moisture
advection from the south into the system. This will ensure the
storms continue right through the period, as the MCS slowly moves
east. As usual, the southern end of the MCS appears to be the area
of greatest concern, as the storms on the south side are the first
to ingest the deep Gulf moisture over the area. This will encourage
the storms to linger and backbuild to the southwest, extending the
duration of the heavy rainfall in those areas. Further, FFGs across
much of the Midwest remain depressed due to recent heavy rainfall,
and soils are wetter than normal. Some drying in between now and
Sunday should help to mitigate flooding somewhat, but the strongest
storms should have no trouble exceeding the FFGs as 2-3 inch/hour
rates are expected. A Moderate Risk remains possible. If one were
to be issued, it appears a band extending west to east along I-70
in Missouri, then following I-64 across southern Illinois, Indiana,
and then east through Cincinnati and northern Kentucky appears most
probable. However, the details of the storms and their placement
remain difficult to pinpoint, especially as this remains outside of
the CAMs range, so additional changes are likely.

...South Dakota...

An MCS, separate from the one going into the Midwest, likely gets
started across South Dakota Saturday night. With dry soils in the
area, the rain with the intial storms then are likely to be
absorbed with only isolated flooding concerns. However, going into
Sunday morning, the redevelopment of the storms across the area
will increase the flooding potential in the area with time. A
southeasterly jet of moisture wrapping around a low over Nebraska
should keep a continuous supply of moisture heading into the
storms, and with that windflow working counter to the southeasterly
movement of the storms, that should work to slow the storms'
forward speed, worsening flooding concerns. Given all this and in
coordination with ABR/Aberdeen, SD and UNR/Rapid City, SD forecast
offices, a Slight Risk area was introduced with this update.

Wegman

...Previous Discussion...

...Midwest...

By the start of the day 3 forecast period a potent shortwave and
related surface low are expected to eject eastward out of the
central Plains into the Midwest. There remains some uncertainty
regarding the speed and latitude of these features, but PWs above
the 90th climatological percentile (per the 00z GEFS) overlapping
with soils likely still recovering from recent heavy rain in the
Midwest will lead to at least scattered flash flooding concerns.
NBM probabilities for at least 2" are very high (between 60-80%)
and cover much of the northern SLGT risk area from MO/IA to OH.
Locally higher totals are likely given the convective environment.
The progressive nature of these storms may end up limiting the
severity of flash flood impacts, but a MDT risk upgrade is possible
should training/back- building elements become more obvious in the
short range updates, particularly along the leading warm front
ahead of the primary surface low.

...Southern Plains, Ozarks, and Lower Ohio Valley...

The setup on Sunday could lead to a southern secondary axis of
heaviest QPF and flash flooding impacts. The southern end of the
Saturday night thunderstorm complex/MCS is likely to sink
southeastward near a trailing cold front and impact areas near the
Ozarks early Sunday. Then, the expectation is for reforming
scattered convection during peak daytime heating and reorganization
of thunderstorms overnight Sunday associated with the LLJ to span
from OK to the Lower Ohio Valley, including northern AR, southern
MO, and western TN/KY. This combines for guidance to currently
depict current QPF amounts of 2-4" and an average localized max of
6". There remains obvious mesoscale uncertainties at this stage,
but with Pws near the 90th climatological percentile and a
favorably oriented west- east frontal boundary, it's possible a MDT
risk upgrade may be needed once CAMs come into forecast range. For
the Lower Ohio Valley in particular, some guidance also highlights thunderstorms associated with the initial warm front lifting
northward, which could add yet another potential for slow-moving
repeating thunderstorms.

Snell
=20

Day 4 and Day 5

Valid 12Z Mon Jun 22 2026 - 12Z Wed Jun 24 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM PORTIONS OF
THE SOUTHERN PLAINS, LOWER MISSISSIPPI AND TENNESSEE VALLEYS, AND
CENTRAL APPALACHIANS ON DAY 4...

2030Z Update...
Ensemble and deterministic runs from the dayshift largely supported
the previously-issued excessive rainfall outlook and discussion.
Changes were minimnal and continued to focus in the same area.

Bann

Previous Discussion...
Day 4 continues to an active pattern through a good portion of the
CONUS, east of the Mississippi with a progressive trough axis
pushing through the Great Lakes and Northeast leading to periods of
moderate to heavy rainfall from the Ohio Valley into the Mid
Atlantic and Northeast. Areas of the Northeast are subject to
thunderstorm prospects with the best chance for flash flooding
likely to occur in the urban footprint from Philadelphia up to
Boston with an expansion inland to the Hudson Valley down through
eastern PA. Current probs off the latest ensembles and National
Blend indicate a large zone of 50-80% probs for >1" across the
aforementioned area above with deterministic outputs closer to
2-2.5" into parts of Southern New England. MRGL risk inherited
remains in effect, but there's potential here for an upgrade as we
move closer to the D4 window, but want to see more of the CAMs to
make that decision.

Across the Southern U.S., heavy precipitation will preclude another
round of convection forming along a quasi-stationary front draped
from the Southern High Plains to the Southeastern CONUS. Probs for

1" are highest in-of the areas of Eastern OK into the Lower

Mississippi and southwestern Tennessee Valleys. Elevated theta_E's
and PWAT anomalies +2 dev. or greater indicate a formidable
environment capable of continued heavy rain potential that will
likely produce rainfall of 2-4", at least in some of the
thunderstorm activity that develops. The focal point along the
front will likely be where the heaviest rain will occur, or at
least be a low-level convergence mechanism that can enhance
regional convection. There's high enough confidence in the location
of convection for the D4 period to overlap with areas that will
have seen several inches the periods prior which led to an upgrade
to a SLGT risk positioned over portions of the Southern Plains
through parts of the Lower Mississippi and neighboring Tennessee
Valleys. The risk extends through the Smokey Mountains up into
parts of the Central Appalachians in eastern KY up into WV as the
convergence regime follows the frontal positioning over these
areas.

Day 5 is a transition period into a more typical summer time regime
for the CONUS with a longwave trough over the Northern U.S. and a
dome of mid and upper ridging positioning itself across the
Southwest. This will cause a persistent northwesterly flow pattern
across the Central and Southern High Plains over into the Lower
Mississippi Valley as progressive shortwave pulses eject out of the
Rockies and ride the prevailing northwesteries in place between the
ridge and trough. This highlights potential for MCS development and
flash flooding scenarios from the Front Range and points southeast
as the steering flow orients between the base of the trough and the northeastern flank of the ridge. This is historically projecting a
case of thunderstorm maturation and upscale growth over the area
between CO/KS down through OK/TX with potentially the Red River
Basin as a focus for thunderstorm activity. Eventually this ends up
migrating into the ArkLaTex and/or Lower Mississippi area which is
showing up in the QPF footprint on ensembles. With this becoming a
more stable signal in the global ensembles and aligning with the
NBM QPF output, a MRGL risk was added to the new D5 to account for
this potential evolution.

Kleebauer
=20

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!6Dh5vpGyUjhtYXN67_VOLPsuu5CbQcDfx95WDyVO0ijP= 1ZzWZcEWHU6BmfB4WBti1RQMFO-QFZDXA2y_8qVwP4U7TYg$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!6Dh5vpGyUjhtYXN67_VOLPsuu5CbQcDfx95WDyVO0ijP= 1ZzWZcEWHU6BmfB4WBti1RQMFO-QFZDXA2y_8qVwaoWlzH0$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!6Dh5vpGyUjhtYXN67_VOLPsuu5CbQcDfx95WDyVO0ijP= 1ZzWZcEWHU6BmfB4WBti1RQMFO-QFZDXA2y_8qVwjDybgF8$=20



$$

=3D =3D =3D
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FOUS30 KWBC 200800
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
400 AM EDT Sat Jun 20 2026

Day 1
Valid 12Z Sat Jun 20 2026 - 12Z Sun Jun 21 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL IN EFFECT FOR
PARTS OF THE CENTRAL PLAINS AND LOWER MISSOURI VALLEY...

...Central Plains and Missouri Valley...

A large area of heavy rain associated with a developing MCS
starting this evening and continuing into early Sunday is expected
to bring widespread heavy rainfall and flash flooding across
portions of the central Plains into the Missouri Valley. The
greatest threat for numerous instances of flash flooding currently
is expected across southeastern Nebraska, northeastern Kansas, and
far northwestern Missouri/southwestern Iowa. Storms are expected
to initiate Saturday afternoon with peak heating over the central
High Plains and ahead of a racing shortwave crossing the Rockies.
Meanwhile, a LLJ of southeasterly flow will increase WAA and pump
deep Gulf moisture up the Plains through the day. This will force
the dryline to race eastward in response. The warm front associated
with the low and the dry line will uplift the deep moisture,
resulting in widespread shower and thunderstorm development across
Nebraska as early as this afternoon. These storms are expected to
grow upscale into an expansive, organized convective system into
the evening and overnight hours that will then track southeasterly
across the risk area.

The latest deterministic guidance shows areal average rainfall
totals along the expected path of the MCS in the 2-4" range with
locally higher amounts of 4-6", more than sufficient to lead to
potentially widespread flash flooding, which has prompted the
level 3/4 Moderate Risk. As is usually the case with convective
systems the exact path and duration will be determined by more
mesoscale details than the guidance can typically pin down. Some
CAMs (like the NAM3k) favor the northern axis of heavy rain across
southeast Nebraska closer to the developing surface low/MCV,
whereas the 00z RRFS favors a southern solution and heaviest
rainfall across central Kansas. Regardless, PWs surging to 2" by
tonight and increased forcing will support rainfall rates within
thunderstorms to be intense and around 2-3"/hr. These rates could
be exacerbated by cell mergers and brief training to quickly lead
to flash flooding concerns. The 00Z REFS and HREF both highlight
neighborhood probabilities of 3" per 6-hrs (above local FFG) around
40-50%+ within the MDT through 12Z Sun and then extending into the
Day 2 period. Should these heavier rates intersect with urban
area, significant impacts from flash flooding cannot be ruled out.

...Eastern Texas through the Southeast...

One more day of scattered slow-moving storms is expected today
across the Deep South between eastern TX and southeast GA/northeast
FL. The lingering frontal boundary draped north of the Gulf Coast
will begin to lift north during the day and leave convection widely
scattered, but with one area of more focused activity between
central MS and coastal southeast GA/northeast FL. This is likely
during the morning and midday hours and supported by most CAMs as
high pressure over the Tennessee Valley keeps the thermal/moisture
gradient rather sharp and focuses ongoing thunderstorm activity
within PWs above 2". Both the 00Z REFS and 00Z HREF highlight
elevated chances (40-50%) for at least 3" in 6-hrs near Birmingham,
AL. This could be an area within the SLGT risk that sees more
severe flash flood impacts should a higher-end scenario develop.
Lingering MCV(s) across eastern TX and the Lower Mississippi Valley
could also add a focus for more organized thunderstorm activity,
while also adding to the short term uncertainty. The soils in this
region remain extremely saturated and sensitive to additional
intense rainfall rates, leading to the potential for scattered
instances of flash flooding and the SLGT risk of excessive
rainfall, even for locations that can typically take 2-3" of rain.

Snell
=20

Day 2
Valid 12Z Sun Jun 21 2026 - 12Z Mon Jun 22 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL IN EFFECT FOR
PARTS OF THE CENTRAL PLAINS, MIDDLE MISSISSIPPI VALLEY, AND OHIO
VALLEY...

...Northern Missouri through central Illinois and Indiana...

By the start of the day 2 forecast period a potent shortwave and
related surface low/MCV are expected to eject eastward out of the
central Plains into the Midwest. There still remains at least some
uncertainty regarding the speed and latitude of these features
(NAM3k a northern outlier for example), but PWs and IVT above the
90th climatological percentile (per the 00z GEFS) overlapping with
soils likely still recovering from recent heavy rain in the Midwest
will likely lead to a swath of scattered flash flooding. A MDT
risk was introduced with the latest outlook, spanning from MO to
central IN. Heavy rain near a strengthening surface low and
increased lift along an eastward stretching warm front across the
Ohio Valley will overlap with saturated soils and swollen rivers
across much of IL and IN. This will be one axis for potentially
widespread flash flooding, with another axis lingering across
southwest MO into eastern KS and possibly a relative minimum in
between (right now most likely centered around central to
southeast MO). This MO/KS potential is associated with the
southwestern tail of an expected MCS, where flow may become
parallel to the outflow boundary/front and promote both training
thunderstorms and redevelopment of storms by Sunday evening.

NBM probabilities for at least 2" remain very high (between
70-90%) and cover much of northern MO, central IL, and central IN.
Locally higher totals (CAMs depict potential for 4-7" totals) are
likely given the convective environment. 00Z HREF and 18Z REFS
probabilities for exceeding 3-hr FFG are around 30-60% across IL
and IN, where antecedent ground conditions are wettest. The
progressive nature of these storms may end up limiting the severity
of flash flood impacts, but coverage of flash flooding impacts is
expected to be widespread enough in the Midwest/Ohio Valley to
warrant the level 3/4 MDT risk upgrade.

...Eastern Kansas to Southwest Missouri...

More information regarding the southern end of the Saturday night
thunderstorm complex/MCS likely to sink southeastward near a
trailing cold front and impact areas near the Ozarks Sunday. 850 mb
flow is expected to become quite convergent extending from central
KS to southern MO, which will likely be the focus for training
convection potential early on and then reforming activity later in
Sunday associated with additional shortwave activity moving
eastward across the Plains. However, there is some uncertainty
surrounding if this boundary can sink further south during the day
and keep storms somewhat progressive. This all combines for
guidance to currently depict current QPF amounts of 3-4" and an
average localized max of 6". This area also includes soils
saturated due to a recent wet weather pattern, with NASA SPoRT-LIS
depicting pockets above the 80th percentile in the 0-40cm soil
moisture layer. Lastly, 00Z REFS and HREF probabilities are
agreeable with 40-70% values for exceeding 3" per 6-hrs.

Snell
=20

Day 3
Valid 12Z Mon Jun 22 2026 - 12Z Tue Jun 23 2026

...THERE IS A SLIGHT RISK IN EFFECT FROM THE OHIO VALLEY TO
SOUTHERN PLAINS...

Day 3 continues to be an active pattern through a good portion of
the CONUS, east of the Mississippi with a progressive trough axis
pushing through the Great Lakes and Northeast leading to periods of
moderate to heavy rainfall from the Ohio Valley into the Mid
Atlantic and Northeast. Areas of the Northeast are subject to
thunderstorm prospects with the best chance for flash flooding
likely to occur in the urban footprint from Philadelphia up to
Boston with an expansion inland to the Hudson Valley down through
eastern PA. Current probs off the latest ensembles and National
Blend indicate a large zone of 30-50% probs for >2" across the
aforementioned area above with deterministic outputs closer to
2-3.5" into parts of Southern New England. MRGL risk inherited
remains in effect, but there's potential here for an upgrade as we
move closer to the D2 window, but want to see more of the CAMs to
make that decision. Limiting factor here remains low instability
and while there is a window for heavier rates to linger for 3 to 6
hours, the system overall is progressive. Some uncertainty also
exists south of central NJ along the eastern Mid-Atlantic regarding
overall coverage of thunderstorms.

Across the Southern U.S., heavy precipitation will preclude another
round of convection forming along a quasi-stationary front draped
from the Southern High Plains to the Southeastern CONUS. Probs for

1" are highest in-of the areas of Eastern OK into the Lower

Mississippi and southwestern Tennessee Valleys. Elevated theta_E's
and PWAT anomalies +2 dev. or greater indicate a formidable
environment capable of continued heavy rain potential that will
likely produce rainfall of 2-4", at least in some of the
thunderstorm activity that develops. The focal point along the
front will likely be where the heaviest rain will occur, or at
least be a low-level convergence mechanism that can enhance
regional convection. There's high enough confidence in the location
of convection for the D3 period to overlap with areas that will
have seen several inches the periods prior which led to a level 2/4
SLGT risk positioned over portions of the Southern Plains through
parts of the Lower Mississippi and neighboring Tennessee. The risk
extends through the Smokey Mountains up into parts of the Central
Appalachians in eastern KY up into WV as the convergence regime
follows the frontal positioning over these areas. Greatest chances
for multiple rounds of slow-moving thunderstorms capable of 2"+
hourly rainfall rates currently appears to be over southeast OK
into central AR and will be monitored closely once CAMs are within
range of the forecast time period.

Snell
=20

Day 4 and Day 5
Valid 12Z Tue Jun 23 2026 - 12Z Thu Jun 25 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FROM PORTIONS OF
THE CENTRAL AND SOUTHERN PLAINS, LOWER MISSISSIPPI VALLEY, AND
SOUTHEASTERN U.S ON BOTH DAY 4 AND DAY 5...

Day 4 is a transition period into a more typical summertime regime
for the CONUS with a longwave trough over the Northern U.S. and a
dome of mid and upper ridging orienting itself across the
southwestern CONUS. Positioning of the trough/ridge pattern will
cause a persistent northwesterly flow within the mid and upper
levels across the Central and Southern High Plains over into the
Lower Mississippi Valley as progressive shortwave pulses eject out
of the Rockies and ride the prevailing northwesterlies in place
between the ridge and trough. This highlights potential for MCS
development and flash flooding scenarios from the Front Range and
points southeast as the steering flow orients between the base of
the trough and the northeastern flank of the ridge. This is
historically projecting a case of thunderstorm maturation and
upscale growth over the area between CO/KS down through OK/TX with
potentially the Red River Basin as a focus for thunderstorm
activity. Eventually, this ends up migrating into the ArkLaTex
and/or Lower Mississippi area which is showing up in the QPF
footprint on ensembles. There has been little variance in the
recent global ensemble suite with the deterministic output also
showing very similar outcomes, at varying magnitudes with the
synoptic evolution generally stable with run-to-run continuity. The
entire setup continues through Day 5, as well, with repetition in
the mid and upper pattern as multiple vorticity maxima slide out of
the Central Rockies and migrate east-southeast through the mean
flow between the trough and ridge setup.

QPF distribution for both days is relatively even, however the D4
period is currently the most aggressive in terms of precipitation
magnitudes depicted as the time frame notes a stronger mid-level
disturbance ejecting out of the Front Range with heavy rain
prospects spanning from southwestern NE down through KS/OK,
eventually into the Lower Mississippi Valley as you work through
the end of D4 into D5. PQPF signatures for >1" of precipitation are
already pushing above 40% at lead for much of the aforementioned
area, a testament to a stable signal for widespread moderate to
heavy rain prospects as both the thermodynamic and kinematic
evolutions remain favorable for the D4 and D5 periods. Expectation
is for eventual upgrades across portions of the outlined area as we
move closer, especially if the signal remains stable and the hi-res deterministic begin outlining the higher rate characteristics for
the precipitation. Greatest risk for an upgrade is likely to occur
where there will be multiple days of convective overlap allowing
for falling FFG's and more susceptible hydrologic impacts as
regional streams and rivers become more prone to flooding. This is
a scenario where we'll be monitoring the evolution closely as more
appreciable impacts are plausible in this synoptic scale
persistence.

Kleebauer
=20

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!_fzpi3M0Q8pwbI6n191EGYPLZwFij3m6iEjZ0t-ykcn5= GaFM7AMibLFGzN_SohUOgoaJKB3Op6yuGB8FSAr-S_tggqQ$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!_fzpi3M0Q8pwbI6n191EGYPLZwFij3m6iEjZ0t-ykcn5= GaFM7AMibLFGzN_SohUOgoaJKB3Op6yuGB8FSAr-n5ESHho$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!_fzpi3M0Q8pwbI6n191EGYPLZwFij3m6iEjZ0t-ykcn5= GaFM7AMibLFGzN_SohUOgoaJKB3Op6yuGB8FSAr-ldSG1pc$=20



$$

=3D =3D =3D
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FOUS30 KWBC 201545
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1145 AM EDT Sat Jun 20 2026

Day 1
Valid 12Z Sat Jun 20 2026 - 12Z Sun Jun 21 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL IN EFFECT FOR
PARTS OF THE CENTRAL PLAINS AND LOWER MISSOURI VALLEY...

...Central Plains and Missouri Valley...

A large area of heavy rain associated with a developing MCS
starting this evening and continuing into early Sunday is expected
to bring widespread heavy rainfall and flash flooding across
portions of the central Plains into the Missouri Valley. The
greatest threat for numerous instances of flash flooding currently
is expected across southeastern Nebraska, northeastern Kansas, and
far northwestern Missouri/southwestern Iowa. Storms are expected
to initiate Saturday afternoon with peak heating over the central
High Plains and ahead of a racing shortwave crossing the Rockies.
Meanwhile, a LLJ of southeasterly flow will increase WAA and pump
deep Gulf moisture up the Plains through the day. This will force
the dryline to race eastward in response. The warm front associated
with the low and the dry line will uplift the deep moisture,
resulting in widespread shower and thunderstorm development across
Nebraska as early as this afternoon. These storms are expected to
grow upscale into an expansive, organized convective system into
the evening and overnight hours that will then track southeasterly
across the risk area.

The latest deterministic guidance shows areal average rainfall
totals along the expected path of the MCS in the 2-4" range with
locally higher amounts of 4-6", more than sufficient to lead to
potentially widespread flash flooding, which has prompted the
level 3/4 Moderate Risk. As is usually the case with convective
systems the exact path and duration will be determined by more
mesoscale details than the guidance can typically pin down. Some
CAMs (like the NAM3k) favor the northern axis of heavy rain across
southeast Nebraska closer to the developing surface low/MCV,
whereas the 00z RRFS favors a southern solution and heaviest
rainfall across central Kansas. Regardless, PWs surging to 2" by
tonight and increased forcing will support rainfall rates within
thunderstorms to be intense and around 2-3"/hr. These rates could
be exacerbated by cell mergers and brief training to quickly lead
to flash flooding concerns. The 00Z REFS and HREF both highlight
neighborhood probabilities of 3" per 6-hrs (above local FFG) around
40-50%+ within the MDT through 12Z Sun and then extending into the
Day 2 period. Should these heavier rates intersect with urban
area, significant impacts from flash flooding cannot be ruled out.

...Eastern Texas through the Southeast...

1600Z Update...

Per collaboration with the affected WFOs, have expanded the Slight
Risk down the Middle and Lower TX Coast (and adjacent inland
counties), based on the current observational/mesoanalysis trends
along with the recent (12Z) high-res CAM trends and HREF
probabilistic suite. Airmass remains primed for highly efficient
rainfall rates, with PWs over 2.25" and mixed-layer CAPEs quite
robust between 2000-3000 J/Kg. All ahead of a slow-moving upper=20
level vort lobe along/inland of the Gulf Coast (MCV over S. TX),=20
where Gulf breezes will enhance the low-level moisture convergence
farther inland.

Hurley

Previous discussion...

One more day of scattered slow-moving storms is expected today=20
across the Deep South between eastern TX and southeast GA/northeast
FL. The lingering frontal boundary draped north of the Gulf Coast=20
will begin to lift north during the day and leave convection widely
scattered, but with one area of more focused activity between=20
central MS and coastal southeast GA/northeast FL. This is likely=20
during the morning and midday hours and supported by most CAMs as=20
high pressure over the Tennessee Valley keeps the thermal/moisture=20
gradient rather sharp and focuses ongoing thunderstorm activity=20
within PWs above 2". Both the 00Z REFS and 00Z HREF highlight
elevated chances (40-50%) for at least 3" in 6-hrs near Birmingham,
AL. This could be an area within the SLGT risk that sees more
severe flash flood impacts should a higher-end scenario develop.

Lingering MCV(s) across eastern TX and the Lower Mississippi Valley
could also add a focus for more organized thunderstorm activity,=20
while also adding to the short term uncertainty. The soils in this=20
region remain extremely saturated and sensitive to additional=20
intense rainfall rates, leading to the potential for scattered=20
instances of flash flooding and the SLGT risk of excessive=20
rainfall, even for locations that can typically take 2-3" of rain.

Snell
=20

Day 2
Valid 12Z Sun Jun 21 2026 - 12Z Mon Jun 22 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL IN EFFECT FOR
PARTS OF THE CENTRAL PLAINS, MIDDLE MISSISSIPPI VALLEY, AND OHIO
VALLEY...

...Northern Missouri through central Illinois and Indiana...

By the start of the day 2 forecast period a potent shortwave and
related surface low/MCV are expected to eject eastward out of the
central Plains into the Midwest. There still remains at least some
uncertainty regarding the speed and latitude of these features
(NAM3k a northern outlier for example), but PWs and IVT above the
90th climatological percentile (per the 00z GEFS) overlapping with
soils likely still recovering from recent heavy rain in the Midwest
will likely lead to a swath of scattered flash flooding. A MDT
risk was introduced with the latest outlook, spanning from MO to
central IN. Heavy rain near a strengthening surface low and
increased lift along an eastward stretching warm front across the
Ohio Valley will overlap with saturated soils and swollen rivers
across much of IL and IN. This will be one axis for potentially
widespread flash flooding, with another axis lingering across
southwest MO into eastern KS and possibly a relative minimum in
between (right now most likely centered around central to
southeast MO). This MO/KS potential is associated with the
southwestern tail of an expected MCS, where flow may become
parallel to the outflow boundary/front and promote both training
thunderstorms and redevelopment of storms by Sunday evening.
NBM probabilities for at least 2" remain very high (between
70-90%) and cover much of northern MO, central IL, and central IN.
Locally higher totals (CAMs depict potential for 4-7" totals) are
likely given the convective environment. 00Z HREF and 18Z REFS
probabilities for exceeding 3-hr FFG are around 30-60% across IL
and IN, where antecedent ground conditions are wettest. The
progressive nature of these storms may end up limiting the severity
of flash flood impacts, but coverage of flash flooding impacts is
expected to be widespread enough in the Midwest/Ohio Valley to
warrant the level 3/4 MDT risk upgrade.

...Eastern Kansas to Southwest Missouri...

More information regarding the southern end of the Saturday night
thunderstorm complex/MCS likely to sink southeastward near a
trailing cold front and impact areas near the Ozarks Sunday. 850 mb
flow is expected to become quite convergent extending from central
KS to southern MO, which will likely be the focus for training
convection potential early on and then reforming activity later in
Sunday associated with additional shortwave activity moving
eastward across the Plains. However, there is some uncertainty
surrounding if this boundary can sink further south during the day
and keep storms somewhat progressive. This all combines for
guidance to currently depict current QPF amounts of 3-4" and an
average localized max of 6". This area also includes soils
saturated due to a recent wet weather pattern, with NASA SPoRT-LIS
depicting pockets above the 80th percentile in the 0-40cm soil
moisture layer. Lastly, 00Z REFS and HREF probabilities are
agreeable with 40-70% values for exceeding 3" per 6-hrs.

Snell

Day 3 Valid 12Z Mon Jun 22 2026 - 12Z Tue Jun 23 2026

...THERE IS A SLIGHT RISK IN EFFECT FROM THE OHIO VALLEY TO
SOUTHERN PLAINS...

Day 3 continues to be an active pattern through a good portion of
the CONUS, east of the Mississippi with a progressive trough axis
pushing through the Great Lakes and Northeast leading to periods of
moderate to heavy rainfall from the Ohio Valley into the Mid
Atlantic and Northeast. Areas of the Northeast are subject to
thunderstorm prospects with the best chance for flash flooding
likely to occur in the urban footprint from Philadelphia up to
Boston with an expansion inland to the Hudson Valley down through
eastern PA. Current probs off the latest ensembles and National
Blend indicate a large zone of 30-50% probs for >2" across the
aforementioned area above with deterministic outputs closer to
2-3.5" into parts of Southern New England. MRGL risk inherited
remains in effect, but there's potential here for an upgrade as we
move closer to the D2 window, but want to see more of the CAMs to
make that decision. Limiting factor here remains low instability
and while there is a window for heavier rates to linger for 3 to 6
hours, the system overall is progressive. Some uncertainty also
exists south of central NJ along the eastern Mid-Atlantic regarding
overall coverage of thunderstorms.

Across the Southern U.S., heavy precipitation will preclude another
round of convection forming along a quasi-stationary front draped
from the Southern High Plains to the Southeastern CONUS. Probs for

1" are highest in-of the areas of Eastern OK into the Lower

Mississippi and southwestern Tennessee Valleys. Elevated theta_E's
and PWAT anomalies +2 dev. or greater indicate a formidable
environment capable of continued heavy rain potential that will
likely produce rainfall of 2-4", at least in some of the
thunderstorm activity that develops. The focal point along the
front will likely be where the heaviest rain will occur, or at
least be a low-level convergence mechanism that can enhance
regional convection. There's high enough confidence in the location
of convection for the D3 period to overlap with areas that will
have seen several inches the periods prior which led to a level 2/4
SLGT risk positioned over portions of the Southern Plains through
parts of the Lower Mississippi and neighboring Tennessee. The risk
extends through the Smokey Mountains up into parts of the Central
Appalachians in eastern KY up into WV as the convergence regime
follows the frontal positioning over these areas. Greatest chances
for multiple rounds of slow-moving thunderstorms capable of 2"+
hourly rainfall rates currently appears to be over southeast OK
into central AR and will be monitored closely once CAMs are within
range of the forecast time period.

Snell

Day 4 and Day 5

Valid 12Z Tue Jun 23 2026 - 12Z Thu Jun 25 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FROM PORTIONS OF
THE CENTRAL AND SOUTHERN PLAINS, LOWER MISSISSIPPI VALLEY, AND
SOUTHEASTERN U.S ON BOTH DAY 4 AND DAY 5...

Day 4 is a transition period into a more typical summertime regime
for the CONUS with a longwave trough over the Northern U.S. and a
dome of mid and upper ridging orienting itself across the
southwestern CONUS. Positioning of the trough/ridge pattern will
cause a persistent northwesterly flow within the mid and upper
levels across the Central and Southern High Plains over into the
Lower Mississippi Valley as progressive shortwave pulses eject out
of the Rockies and ride the prevailing northwesterlies in place
between the ridge and trough. This highlights potential for MCS
development and flash flooding scenarios from the Front Range and
points southeast as the steering flow orients between the base of
the trough and the northeastern flank of the ridge. This is
historically projecting a case of thunderstorm maturation and
upscale growth over the area between CO/KS down through OK/TX with
potentially the Red River Basin as a focus for thunderstorm
activity. Eventually, this ends up migrating into the ArkLaTex
and/or Lower Mississippi area which is showing up in the QPF
footprint on ensembles. There has been little variance in the
recent global ensemble suite with the deterministic output also
showing very similar outcomes, at varying magnitudes with the
synoptic evolution generally stable with run-to-run continuity. The
entire setup continues through Day 5, as well, with repetition in
the mid and upper pattern as multiple vorticity maxima slide out of
the Central Rockies and migrate east-southeast through the mean
flow between the trough and ridge setup.

QPF distribution for both days is relatively even, however the D4
period is currently the most aggressive in terms of precipitation
magnitudes depicted as the time frame notes a stronger mid-level
disturbance ejecting out of the Front Range with heavy rain
prospects spanning from southwestern NE down through KS/OK,
eventually into the Lower Mississippi Valley as you work through
the end of D4 into D5. PQPF signatures for >1" of precipitation are
already pushing above 40% at lead for much of the aforementioned
area, a testament to a stable signal for widespread moderate to
heavy rain prospects as both the thermodynamic and kinematic
evolutions remain favorable for the D4 and D5 periods. Expectation
is for eventual upgrades across portions of the outlined area as we
move closer, especially if the signal remains stable and the hi-res deterministic begin outlining the higher rate characteristics for
the precipitation. Greatest risk for an upgrade is likely to occur
where there will be multiple days of convective overlap allowing
for falling FFG's and more susceptible hydrologic impacts as
regional streams and rivers become more prone to flooding. This is
a scenario where we'll be monitoring the evolution closely as more
appreciable impacts are plausible in this synoptic scale
persistence.

Kleebauer

Day 1 threat area:=20 https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt= __;!!DZ3fjg!-Wrx7exhHGuNKAFRzfAwrdnYaBXAT3g30MIvuUJqFOknhECZXFIYa64pPASsaYc= 6OM04WbCCgXQnORfUTAw3L8N71PQ$=20
Day 2 threat area:=20 https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt= __;!!DZ3fjg!-Wrx7exhHGuNKAFRzfAwrdnYaBXAT3g30MIvuUJqFOknhECZXFIYa64pPASsaYc= 6OM04WbCCgXQnORfUTAw3n2gat5E$=20
Day 3 threat area:=20 https://urldefense.com/v3/__https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt= __;!!DZ3fjg!-Wrx7exhHGuNKAFRzfAwrdnYaBXAT3g30MIvuUJqFOknhECZXFIYa64pPASsaYc= 6OM04WbCCgXQnORfUTAw3gUEvqzg$=20

$$

=3D =3D =3D
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FOUS30 KWBC 201650
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1250 PM EDT Sat Jun 20 2026

Day 1
Valid 16Z Sat Jun 20 2026 - 12Z Sun Jun 21 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL IN EFFECT FOR
PARTS OF THE CENTRAL PLAINS AND LOWER MISSOURI VALLEY...

...Central Plains and Missouri Valley...

A large area of heavy rain associated with a developing MCS
starting this evening and continuing into early Sunday is expected
to bring widespread heavy rainfall and flash flooding across
portions of the central Plains into the Missouri Valley. The
greatest threat for numerous instances of flash flooding currently
is expected across southeastern Nebraska, northeastern Kansas, and
far northwestern Missouri/southwestern Iowa. Storms are expected
to initiate Saturday afternoon with peak heating over the central
High Plains and ahead of a racing shortwave crossing the Rockies.
Meanwhile, a LLJ of southeasterly flow will increase WAA and pump
deep Gulf moisture up the Plains through the day. This will force
the dryline to race eastward in response. The warm front associated
with the low and the dry line will uplift the deep moisture,
resulting in widespread shower and thunderstorm development across
Nebraska as early as this afternoon. These storms are expected to
grow upscale into an expansive, organized convective system into
the evening and overnight hours that will then track southeasterly
across the risk area.

The latest deterministic guidance shows areal average rainfall
totals along the expected path of the MCS in the 2-4" range with
locally higher amounts of 4-6", more than sufficient to lead to
potentially widespread flash flooding, which has prompted the
level 3/4 Moderate Risk. As is usually the case with convective
systems the exact path and duration will be determined by more
mesoscale details than the guidance can typically pin down. Some
CAMs (like the NAM3k) favor the northern axis of heavy rain across
southeast Nebraska closer to the developing surface low/MCV,
whereas the 00z RRFS favors a southern solution and heaviest
rainfall across central Kansas. Regardless, PWs surging to 2" by
tonight and increased forcing will support rainfall rates within
thunderstorms to be intense and around 2-3"/hr. These rates could
be exacerbated by cell mergers and brief training to quickly lead
to flash flooding concerns. The 00Z REFS and HREF both highlight
neighborhood probabilities of 3" per 6-hrs (above local FFG) around
40-50%+ within the MDT through 12Z Sun and then extending into the
Day 2 period. Should these heavier rates intersect with urban
area, significant impacts from flash flooding cannot be ruled out.

...Eastern Texas through the Southeast...

1600Z Update...

Per collaboration with the affected WFOs, have expanded the Slight
Risk down the Middle and Lower TX Coast (and adjacent inland
counties), based on the current observational/mesoanalysis trends
along with the recent (12Z) high-res CAM trends and HREF
probabilistic suite. Airmass remains primed for highly efficient
rainfall rates, with PWs over 2.25" and mixed-layer CAPEs quite
robust between 2000-3000 J/Kg. All ahead of a slow-moving upper
level vort lobe along/inland of the Gulf Coast (MCV over S. TX),
where Gulf breezes will enhance the low-level moisture convergence
farther inland.

Hurley

Previous discussion...

One more day of scattered slow-moving storms is expected today
across the Deep South between eastern TX and southeast GA/northeast
FL. The lingering frontal boundary draped north of the Gulf Coast
will begin to lift north during the day and leave convection widely
scattered, but with one area of more focused activity between
central MS and coastal southeast GA/northeast FL. This is likely
during the morning and midday hours and supported by most CAMs as
high pressure over the Tennessee Valley keeps the thermal/moisture
gradient rather sharp and focuses ongoing thunderstorm activity
within PWs above 2". Both the 00Z REFS and 00Z HREF highlight
elevated chances (40-50%) for at least 3" in 6-hrs near Birmingham,
AL. This could be an area within the SLGT risk that sees more
severe flash flood impacts should a higher-end scenario develop.

Lingering MCV(s) across eastern TX and the Lower Mississippi Valley
could also add a focus for more organized thunderstorm activity,
while also adding to the short term uncertainty. The soils in this
region remain extremely saturated and sensitive to additional
intense rainfall rates, leading to the potential for scattered
instances of flash flooding and the SLGT risk of excessive
rainfall, even for locations that can typically take 2-3" of rain.

Snell
=20

Day 2
Valid 12Z Sun Jun 21 2026 - 12Z Mon Jun 22 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL IN EFFECT FOR
PARTS OF THE CENTRAL PLAINS, MIDDLE MISSISSIPPI VALLEY, AND OHIO
VALLEY...

...Northern Missouri through central Illinois and Indiana...

By the start of the day 2 forecast period a potent shortwave and
related surface low/MCV are expected to eject eastward out of the
central Plains into the Midwest. There still remains at least some
uncertainty regarding the speed and latitude of these features
(NAM3k a northern outlier for example), but PWs and IVT above the
90th climatological percentile (per the 00z GEFS) overlapping with
soils likely still recovering from recent heavy rain in the Midwest
will likely lead to a swath of scattered flash flooding. A MDT
risk was introduced with the latest outlook, spanning from MO to
central IN. Heavy rain near a strengthening surface low and
increased lift along an eastward stretching warm front across the
Ohio Valley will overlap with saturated soils and swollen rivers
across much of IL and IN. This will be one axis for potentially
widespread flash flooding, with another axis lingering across
southwest MO into eastern KS and possibly a relative minimum in
between (right now most likely centered around central to
southeast MO). This MO/KS potential is associated with the
southwestern tail of an expected MCS, where flow may become
parallel to the outflow boundary/front and promote both training
thunderstorms and redevelopment of storms by Sunday evening.
NBM probabilities for at least 2" remain very high (between
70-90%) and cover much of northern MO, central IL, and central IN.
Locally higher totals (CAMs depict potential for 4-7" totals) are
likely given the convective environment. 00Z HREF and 18Z REFS
probabilities for exceeding 3-hr FFG are around 30-60% across IL
and IN, where antecedent ground conditions are wettest. The
progressive nature of these storms may end up limiting the severity
of flash flood impacts, but coverage of flash flooding impacts is
expected to be widespread enough in the Midwest/Ohio Valley to
warrant the level 3/4 MDT risk upgrade.

...Eastern Kansas to Southwest Missouri...

More information regarding the southern end of the Saturday night
thunderstorm complex/MCS likely to sink southeastward near a
trailing cold front and impact areas near the Ozarks Sunday. 850 mb
flow is expected to become quite convergent extending from central
KS to southern MO, which will likely be the focus for training
convection potential early on and then reforming activity later in
Sunday associated with additional shortwave activity moving
eastward across the Plains. However, there is some uncertainty
surrounding if this boundary can sink further south during the day
and keep storms somewhat progressive. This all combines for
guidance to currently depict current QPF amounts of 3-4" and an
average localized max of 6". This area also includes soils
saturated due to a recent wet weather pattern, with NASA SPoRT-LIS
depicting pockets above the 80th percentile in the 0-40cm soil
moisture layer. Lastly, 00Z REFS and HREF probabilities are
agreeable with 40-70% values for exceeding 3" per 6-hrs.

Snell
=20

Day 3
Valid 12Z Mon Jun 22 2026 - 12Z Tue Jun 23 2026

...THERE IS A SLIGHT RISK IN EFFECT FROM THE OHIO VALLEY TO
SOUTHERN PLAINS...

Day 3 continues to be an active pattern through a good portion of
the CONUS, east of the Mississippi with a progressive trough axis
pushing through the Great Lakes and Northeast leading to periods of
moderate to heavy rainfall from the Ohio Valley into the Mid
Atlantic and Northeast. Areas of the Northeast are subject to
thunderstorm prospects with the best chance for flash flooding
likely to occur in the urban footprint from Philadelphia up to
Boston with an expansion inland to the Hudson Valley down through
eastern PA. Current probs off the latest ensembles and National
Blend indicate a large zone of 30-50% probs for >2" across the
aforementioned area above with deterministic outputs closer to
2-3.5" into parts of Southern New England. MRGL risk inherited
remains in effect, but there's potential here for an upgrade as we
move closer to the D2 window, but want to see more of the CAMs to
make that decision. Limiting factor here remains low instability
and while there is a window for heavier rates to linger for 3 to 6
hours, the system overall is progressive. Some uncertainty also
exists south of central NJ along the eastern Mid-Atlantic regarding
overall coverage of thunderstorms.

Across the Southern U.S., heavy precipitation will preclude another
round of convection forming along a quasi-stationary front draped
from the Southern High Plains to the Southeastern CONUS. Probs for

1" are highest in-of the areas of Eastern OK into the Lower

Mississippi and southwestern Tennessee Valleys. Elevated theta_E's
and PWAT anomalies +2 dev. or greater indicate a formidable
environment capable of continued heavy rain potential that will
likely produce rainfall of 2-4", at least in some of the
thunderstorm activity that develops. The focal point along the
front will likely be where the heaviest rain will occur, or at
least be a low-level convergence mechanism that can enhance
regional convection. There's high enough confidence in the location
of convection for the D3 period to overlap with areas that will
have seen several inches the periods prior which led to a level 2/4
SLGT risk positioned over portions of the Southern Plains through
parts of the Lower Mississippi and neighboring Tennessee. The risk
extends through the Smokey Mountains up into parts of the Central
Appalachians in eastern KY up into WV as the convergence regime
follows the frontal positioning over these areas. Greatest chances
for multiple rounds of slow-moving thunderstorms capable of 2"+
hourly rainfall rates currently appears to be over southeast OK
into central AR and will be monitored closely once CAMs are within
range of the forecast time period.

Snell
=20

Day 4 and Day 5

Valid 12Z Tue Jun 23 2026 - 12Z Thu Jun 25 2026
...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FROM PORTIONS OF
THE CENTRAL AND SOUTHERN PLAINS, LOWER MISSISSIPPI VALLEY, AND
SOUTHEASTERN U.S ON BOTH DAY 4 AND DAY 5...
Day 4 is a transition period into a more typical summertime regime
for the CONUS with a longwave trough over the Northern U.S. and a
dome of mid and upper ridging orienting itself across the
southwestern CONUS. Positioning of the trough/ridge pattern will
cause a persistent northwesterly flow within the mid and upper
levels across the Central and Southern High Plains over into the
Lower Mississippi Valley as progressive shortwave pulses eject out
of the Rockies and ride the prevailing northwesterlies in place
between the ridge and trough. This highlights potential for MCS
development and flash flooding scenarios from the Front Range and
points southeast as the steering flow orients between the base of
the trough and the northeastern flank of the ridge. This is
historically projecting a case of thunderstorm maturation and
upscale growth over the area between CO/KS down through OK/TX with
potentially the Red River Basin as a focus for thunderstorm
activity. Eventually, this ends up migrating into the ArkLaTex
and/or Lower Mississippi area which is showing up in the QPF
footprint on ensembles. There has been little variance in the
recent global ensemble suite with the deterministic output also
showing very similar outcomes, at varying magnitudes with the
synoptic evolution generally stable with run-to-run continuity. The
entire setup continues through Day 5, as well, with repetition in
the mid and upper pattern as multiple vorticity maxima slide out of
the Central Rockies and migrate east-southeast through the mean
flow between the trough and ridge setup.
QPF distribution for both days is relatively even, however the D4
period is currently the most aggressive in terms of precipitation
magnitudes depicted as the time frame notes a stronger mid-level
disturbance ejecting out of the Front Range with heavy rain
prospects spanning from southwestern NE down through KS/OK,
eventually into the Lower Mississippi Valley as you work through
the end of D4 into D5. PQPF signatures for >1" of precipitation are
already pushing above 40% at lead for much of the aforementioned
area, a testament to a stable signal for widespread moderate to
heavy rain prospects as both the thermodynamic and kinematic
evolutions remain favorable for the D4 and D5 periods. Expectation
is for eventual upgrades across portions of the outlined area as we
move closer, especially if the signal remains stable and the hi-res deterministic begin outlining the higher rate characteristics for
the precipitation. Greatest risk for an upgrade is likely to occur
where there will be multiple days of convective overlap allowing
for falling FFG's and more susceptible hydrologic impacts as
regional streams and rivers become more prone to flooding. This is
a scenario where we'll be monitoring the evolution closely as more
appreciable impacts are plausible in this synoptic scale
persistence.
Kleebauer
=20

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!-RI1P6fJwCZp_BIgsSHZZo3W1DebLvUn1ogexZOmaWK4= HidC9vmRGddhy8WNXf34OfyTTwaIcegVbbNB6fm9asZUEJk$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!-RI1P6fJwCZp_BIgsSHZZo3W1DebLvUn1ogexZOmaWK4= HidC9vmRGddhy8WNXf34OfyTTwaIcegVbbNB6fm902zFrCo$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!-RI1P6fJwCZp_BIgsSHZZo3W1DebLvUn1ogexZOmaWK4= HidC9vmRGddhy8WNXf34OfyTTwaIcegVbbNB6fm9TftPwCk$=20



$$

=3D =3D =3D
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--- SBBSecho 3.28-Linux
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FOUS30 KWBC 201947
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
347 PM EDT Sat Jun 20 2026

Day 1
Valid 16Z Sat Jun 20 2026 - 12Z Sun Jun 21 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL IN EFFECT FOR
PARTS OF THE CENTRAL PLAINS AND LOWER MISSOURI VALLEY...

...Central Plains and Missouri Valley...

A large area of heavy rain associated with a developing MCS
starting this evening and continuing into early Sunday is expected
to bring widespread heavy rainfall and flash flooding across
portions of the central Plains into the Missouri Valley. The
greatest threat for numerous instances of flash flooding currently
is expected across southeastern Nebraska, northeastern Kansas, and
far northwestern Missouri/southwestern Iowa. Storms are expected
to initiate Saturday afternoon with peak heating over the central
High Plains and ahead of a racing shortwave crossing the Rockies.
Meanwhile, a LLJ of southeasterly flow will increase WAA and pump
deep Gulf moisture up the Plains through the day. This will force
the dryline to race eastward in response. The warm front associated
with the low and the dry line will uplift the deep moisture,
resulting in widespread shower and thunderstorm development across
Nebraska as early as this afternoon. These storms are expected to
grow upscale into an expansive, organized convective system into
the evening and overnight hours that will then track southeasterly
across the risk area.

The latest deterministic guidance shows areal average rainfall
totals along the expected path of the MCS in the 2-4" range with
locally higher amounts of 4-6", more than sufficient to lead to
potentially widespread flash flooding, which has prompted the
level 3/4 Moderate Risk. As is usually the case with convective
systems the exact path and duration will be determined by more
mesoscale details than the guidance can typically pin down. Some
CAMs (like the NAM3k) favor the northern axis of heavy rain across
southeast Nebraska closer to the developing surface low/MCV,
whereas the 00z RRFS favors a southern solution and heaviest
rainfall across central Kansas. Regardless, PWs surging to 2" by
tonight and increased forcing will support rainfall rates within
thunderstorms to be intense and around 2-3"/hr. These rates could
be exacerbated by cell mergers and brief training to quickly lead
to flash flooding concerns. The 00Z REFS and HREF both highlight
neighborhood probabilities of 3" per 6-hrs (above local FFG) around
40-50%+ within the MDT through 12Z Sun and then extending into the
Day 2 period. Should these heavier rates intersect with urban
area, significant impacts from flash flooding cannot be ruled out.

...Eastern Texas through the Southeast...

1600Z Update...

Per collaboration with the affected WFOs, have expanded the Slight
Risk down the Middle and Lower TX Coast (and adjacent inland
counties), based on the current observational/mesoanalysis trends
along with the recent (12Z) high-res CAM trends and HREF
probabilistic suite. Airmass remains primed for highly efficient
rainfall rates, with PWs over 2.25" and mixed-layer CAPEs quite
robust between 2000-3000 J/Kg. All ahead of a slow-moving upper
level vort lobe along/inland of the Gulf Coast (MCV over S. TX),
where Gulf breezes will enhance the low-level moisture convergence
farther inland.

Hurley

Previous discussion...

One more day of scattered slow-moving storms is expected today
across the Deep South between eastern TX and southeast GA/northeast
FL. The lingering frontal boundary draped north of the Gulf Coast
will begin to lift north during the day and leave convection widely
scattered, but with one area of more focused activity between
central MS and coastal southeast GA/northeast FL. This is likely
during the morning and midday hours and supported by most CAMs as
high pressure over the Tennessee Valley keeps the thermal/moisture
gradient rather sharp and focuses ongoing thunderstorm activity
within PWs above 2". Both the 00Z REFS and 00Z HREF highlight
elevated chances (40-50%) for at least 3" in 6-hrs near Birmingham,
AL. This could be an area within the SLGT risk that sees more
severe flash flood impacts should a higher-end scenario develop.

Lingering MCV(s) across eastern TX and the Lower Mississippi Valley
could also add a focus for more organized thunderstorm activity,
while also adding to the short term uncertainty. The soils in this
region remain extremely saturated and sensitive to additional
intense rainfall rates, leading to the potential for scattered
instances of flash flooding and the SLGT risk of excessive
rainfall, even for locations that can typically take 2-3" of rain.

Snell
=20

Day 2
Valid 12Z Sun Jun 21 2026 - 12Z Mon Jun 22 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL IN EFFECT FOR
PARTS OF THE CENTRAL PLAINS, MIDDLE MISSISSIPPI VALLEY, AND OHIO
VALLEY...

...2000 UTC update...

For the most part, the outlook areas on Day 2 are largely intact.
Based on the latest (12Z) suite of deterministic and probabilistic
guidance, including CAMs, have nudged the southern periphery of the
Moderate Risk a tad farther south across eastern MO and southern
IL-IN. A bit of a messy setup ahead of the front, with multiple
meso-convective enhanced shortwaves embedded within the broader
upper trough. Because of this, expect a multi-modal heavy rainfall
footprint north-south when all is said and done. That said,
forecast confidence in deciphering such deterministic details at
this stage given the convective component is low, and as a result
for now it's probably best to defer to later shifts with tightening
up the Moderate Risk area.

Otherwise, the trends support a small southeast shift in the Slight
Risk over the Northern Plains (SD-northeast NE). Lastly, based on
the antecedent soils and likelihood of additional activity
associated along a lingering vort lobe (enhanced by Gulf breezes),
have also expanded the Marginal Risk area to the Middle-Upper TX
Coast to portions of the central Gulf Coast.

Hurley


Original discussion below..

...Northern Missouri through central Illinois and Indiana...

By the start of the day 2 forecast period a potent shortwave and
related surface low/MCV are expected to eject eastward out of the
central Plains into the Midwest. There still remains at least some
uncertainty regarding the speed and latitude of these features
(NAM3k a northern outlier for example), but PWs and IVT above the
90th climatological percentile (per the 00z GEFS) overlapping with
soils likely still recovering from recent heavy rain in the Midwest
will likely lead to a swath of scattered flash flooding. A MDT
risk was introduced with the latest outlook, spanning from MO to
central IN. Heavy rain near a strengthening surface low and
increased lift along an eastward stretching warm front across the
Ohio Valley will overlap with saturated soils and swollen rivers
across much of IL and IN. This will be one axis for potentially
widespread flash flooding, with another axis lingering across
southwest MO into eastern KS and possibly a relative minimum in
between (right now most likely centered around central to
southeast MO). This MO/KS potential is associated with the
southwestern tail of an expected MCS, where flow may become
parallel to the outflow boundary/front and promote both training
thunderstorms and redevelopment of storms by Sunday evening.
NBM probabilities for at least 2" remain very high (between
70-90%) and cover much of northern MO, central IL, and central IN.
Locally higher totals (CAMs depict potential for 4-7" totals) are
likely given the convective environment. 00Z HREF and 18Z REFS
probabilities for exceeding 3-hr FFG are around 30-60% across IL
and IN, where antecedent ground conditions are wettest. The
progressive nature of these storms may end up limiting the severity
of flash flood impacts, but coverage of flash flooding impacts is
expected to be widespread enough in the Midwest/Ohio Valley to
warrant the level 3/4 MDT risk upgrade.

...Eastern Kansas to Southwest Missouri...

More information regarding the southern end of the Saturday night
thunderstorm complex/MCS likely to sink southeastward near a
trailing cold front and impact areas near the Ozarks Sunday. 850 mb
flow is expected to become quite convergent extending from central
KS to southern MO, which will likely be the focus for training
convection potential early on and then reforming activity later in
Sunday associated with additional shortwave activity moving
eastward across the Plains. However, there is some uncertainty
surrounding if this boundary can sink further south during the day
and keep storms somewhat progressive. This all combines for
guidance to currently depict current QPF amounts of 3-4" and an
average localized max of 6". This area also includes soils
saturated due to a recent wet weather pattern, with NASA SPoRT-LIS
depicting pockets above the 80th percentile in the 0-40cm soil
moisture layer. Lastly, 00Z REFS and HREF probabilities are
agreeable with 40-70% values for exceeding 3" per 6-hrs.
Snell
=20

Day 3
Valid 12Z Mon Jun 22 2026 - 12Z Tue Jun 23 2026

...THERE IS A SLIGHT RISK IN EFFECT FROM THE OHIO VALLEY TO
SOUTHERN PLAINS...

...2000 UTC Update....

The notable change made to the Day 3 ERO was to expand the Slight
Risk. The main driver was the favorable deep-layer moisture
profiles per the latest guidance, effectively shifting the axis of
2-2.25" PWATs into the Mid Atlantic and southern New England.
Instability at this point appears lacking, however in similar
patterns (per the ERO first guess fields) highly-efficient rainfall
rates in late June will more likely lead to more issues (perhaps
more than just isolated) across the urban corridors and other areas
susceptible to flash flooding. At this point, the EFI per last
night's 00Z ECMWF is around 0.8, which along with PWATs near 2
standard deviations above normal, would certainly support an
upgrade to at least a low-end Slight Risk over these areas (at
least 15% 40km neighborhood probability).

Hurley

Original discussion below..

Day 3 continues to be an active pattern through a good portion of
the CONUS, east of the Mississippi with a progressive trough axis
pushing through the Great Lakes and Northeast leading to periods of
moderate to heavy rainfall from the Ohio Valley into the Mid
Atlantic and Northeast. Areas of the Northeast are subject to
thunderstorm prospects with the best chance for flash flooding
likely to occur in the urban footprint from Philadelphia up to
Boston with an expansion inland to the Hudson Valley down through
eastern PA. Current probs off the latest ensembles and National
Blend indicate a large zone of 30-50% probs for >2" across the
aforementioned area above with deterministic outputs closer to
2-3.5" into parts of Southern New England. MRGL risk inherited
remains in effect, but there's potential here for an upgrade as we
move closer to the D2 window, but want to see more of the CAMs to
make that decision. Limiting factor here remains low instability
and while there is a window for heavier rates to linger for 3 to 6
hours, the system overall is progressive. Some uncertainty also
exists south of central NJ along the eastern Mid-Atlantic regarding
overall coverage of thunderstorms.

Across the Southern U.S., heavy precipitation will preclude another
round of convection forming along a quasi-stationary front draped
from the Southern High Plains to the Southeastern CONUS. Probs for

1" are highest in-of the areas of Eastern OK into the Lower

Mississippi and southwestern Tennessee Valleys. Elevated theta_E's
and PWAT anomalies +2 dev. or greater indicate a formidable
environment capable of continued heavy rain potential that will
likely produce rainfall of 2-4", at least in some of the
thunderstorm activity that develops. The focal point along the
front will likely be where the heaviest rain will occur, or at
least be a low-level convergence mechanism that can enhance
regional convection. There's high enough confidence in the location
of convection for the D3 period to overlap with areas that will
have seen several inches the periods prior which led to a level 2/4
SLGT risk positioned over portions of the Southern Plains through
parts of the Lower Mississippi and neighboring Tennessee. The risk
extends through the Smokey Mountains up into parts of the Central
Appalachians in eastern KY up into WV as the convergence regime
follows the frontal positioning over these areas. Greatest chances
for multiple rounds of slow-moving thunderstorms capable of 2"+
hourly rainfall rates currently appears to be over southeast OK
into central AR and will be monitored closely once CAMs are within
range of the forecast time period.

Snell
=20

Day 4 and Day 5
Valid 12Z Tue Jun 23 2026 - 12Z Thu Jun 25 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FROM PORTIONS OF
THE CENTRAL AND SOUTHERN PLAINS, LOWER MISSISSIPPI VALLEY, AND
SOUTHEASTERN U.S ON BOTH DAY 4 AND DAY 5...

Day 4 is a transition period into a more typical summertime regime
for the CONUS with a longwave trough over the Northern U.S. and a
dome of mid and upper ridging orienting itself across the
southwestern CONUS. Positioning of the trough/ridge pattern will
cause a persistent northwesterly flow within the mid and upper
levels across the Central and Southern High Plains over into the
Lower Mississippi Valley as progressive shortwave pulses eject out
of the Rockies and ride the prevailing northwesterlies in place
between the ridge and trough. This highlights potential for MCS
development and flash flooding scenarios from the Front Range and
points southeast as the steering flow orients between the base of
the trough and the northeastern flank of the ridge. This is
historically projecting a case of thunderstorm maturation and
upscale growth over the area between CO/KS down through OK/TX with
potentially the Red River Basin as a focus for thunderstorm
activity. Eventually, this ends up migrating into the ArkLaTex
and/or Lower Mississippi area which is showing up in the QPF
footprint on ensembles. There has been little variance in the
recent global ensemble suite with the deterministic output also
showing very similar outcomes, at varying magnitudes with the
synoptic evolution generally stable with run-to-run continuity. The
entire setup continues through Day 5, as well, with repetition in
the mid and upper pattern as multiple vorticity maxima slide out of
the Central Rockies and migrate east-southeast through the mean
flow between the trough and ridge setup.

QPF distribution for both days is relatively even, however the D4
period is currently the most aggressive in terms of precipitation
magnitudes depicted as the time frame notes a stronger mid-level
disturbance ejecting out of the Front Range with heavy rain
prospects spanning from southwestern NE down through KS/OK,
eventually into the Lower Mississippi Valley as you work through
the end of D4 into D5. PQPF signatures for >1" of precipitation are
already pushing above 40% at lead for much of the aforementioned
area, a testament to a stable signal for widespread moderate to
heavy rain prospects as both the thermodynamic and kinematic
evolutions remain favorable for the D4 and D5 periods. Expectation
is for eventual upgrades across portions of the outlined area as we
move closer, especially if the signal remains stable and the hi-res deterministic begin outlining the higher rate characteristics for
the precipitation. Greatest risk for an upgrade is likely to occur
where there will be multiple days of convective overlap allowing
for falling FFG's and more susceptible hydrologic impacts as
regional streams and rivers become more prone to flooding. This is
a scenario where we'll be monitoring the evolution closely as more
appreciable impacts are plausible in this synoptic scale
persistence.

Kleebauer
=20

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!4xRpXPrO2FTiyQePOyDHxT-W2esyG9Tvz1chRapyV3HX= 0mTSmiAEuuC7UVY560pwEP1guNWKiFOTNEAV2cr9hXOyWV8$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!4xRpXPrO2FTiyQePOyDHxT-W2esyG9Tvz1chRapyV3HX= 0mTSmiAEuuC7UVY560pwEP1guNWKiFOTNEAV2cr9Clqx5_M$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!4xRpXPrO2FTiyQePOyDHxT-W2esyG9Tvz1chRapyV3HX= 0mTSmiAEuuC7UVY560pwEP1guNWKiFOTNEAV2cr9_xFRVdE$=20



$$

=3D =3D =3D
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FOUS30 KWBC 202021
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
421 PM EDT Sat Jun 20 2026

Day 1
Valid 16Z Sat Jun 20 2026 - 12Z Sun Jun 21 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL IN EFFECT FOR
PARTS OF THE CENTRAL PLAINS AND LOWER MISSOURI VALLEY...

...Central Plains and Missouri Valley...

A large area of heavy rain associated with a developing MCS
starting this evening and continuing into early Sunday is expected
to bring widespread heavy rainfall and flash flooding across
portions of the central Plains into the Missouri Valley. The
greatest threat for numerous instances of flash flooding currently
is expected across southeastern Nebraska, northeastern Kansas, and
far northwestern Missouri/southwestern Iowa. Storms are expected
to initiate Saturday afternoon with peak heating over the central
High Plains and ahead of a racing shortwave crossing the Rockies.
Meanwhile, a LLJ of southeasterly flow will increase WAA and pump
deep Gulf moisture up the Plains through the day. This will force
the dryline to race eastward in response. The warm front associated
with the low and the dry line will uplift the deep moisture,
resulting in widespread shower and thunderstorm development across
Nebraska as early as this afternoon. These storms are expected to
grow upscale into an expansive, organized convective system into
the evening and overnight hours that will then track southeasterly
across the risk area.

The latest deterministic guidance shows areal average rainfall
totals along the expected path of the MCS in the 2-4" range with
locally higher amounts of 4-6", more than sufficient to lead to
potentially widespread flash flooding, which has prompted the
level 3/4 Moderate Risk. As is usually the case with convective
systems the exact path and duration will be determined by more
mesoscale details than the guidance can typically pin down. Some
CAMs (like the NAM3k) favor the northern axis of heavy rain across
southeast Nebraska closer to the developing surface low/MCV,
whereas the 00z RRFS favors a southern solution and heaviest
rainfall across central Kansas. Regardless, PWs surging to 2" by
tonight and increased forcing will support rainfall rates within
thunderstorms to be intense and around 2-3"/hr. These rates could
be exacerbated by cell mergers and brief training to quickly lead
to flash flooding concerns. The 00Z REFS and HREF both highlight
neighborhood probabilities of 3" per 6-hrs (above local FFG) around
40-50%+ within the MDT through 12Z Sun and then extending into the
Day 2 period. Should these heavier rates intersect with urban
area, significant impacts from flash flooding cannot be ruled out.

...Eastern Texas through the Southeast...

1600Z Update...

Per collaboration with the affected WFOs, have expanded the Slight
Risk down the Middle and Lower TX Coast (and adjacent inland
counties), based on the current observational/mesoanalysis trends
along with the recent (12Z) high-res CAM trends and HREF
probabilistic suite. Airmass remains primed for highly efficient
rainfall rates, with PWs over 2.25" and mixed-layer CAPEs quite
robust between 2000-3000 J/Kg. All ahead of a slow-moving upper
level vort lobe along/inland of the Gulf Coast (MCV over S. TX),
where Gulf breezes will enhance the low-level moisture convergence
farther inland.

Hurley

Previous discussion...

One more day of scattered slow-moving storms is expected today
across the Deep South between eastern TX and southeast GA/northeast
FL. The lingering frontal boundary draped north of the Gulf Coast
will begin to lift north during the day and leave convection widely
scattered, but with one area of more focused activity between
central MS and coastal southeast GA/northeast FL. This is likely
during the morning and midday hours and supported by most CAMs as
high pressure over the Tennessee Valley keeps the thermal/moisture
gradient rather sharp and focuses ongoing thunderstorm activity
within PWs above 2". Both the 00Z REFS and 00Z HREF highlight
elevated chances (40-50%) for at least 3" in 6-hrs near Birmingham,
AL. This could be an area within the SLGT risk that sees more
severe flash flood impacts should a higher-end scenario develop.

Lingering MCV(s) across eastern TX and the Lower Mississippi Valley
could also add a focus for more organized thunderstorm activity,
while also adding to the short term uncertainty. The soils in this
region remain extremely saturated and sensitive to additional
intense rainfall rates, leading to the potential for scattered
instances of flash flooding and the SLGT risk of excessive
rainfall, even for locations that can typically take 2-3" of rain.

Snell
=20

Day 2
Valid 12Z Sun Jun 21 2026 - 12Z Mon Jun 22 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL IN EFFECT FOR
PARTS OF THE CENTRAL PLAINS, MIDDLE MISSISSIPPI VALLEY, AND OHIO
VALLEY...

...2000 UTC update...

For the most part, the outlook areas on Day 2 are largely intact.
Based on the latest (12Z) suite of deterministic and probabilistic
guidance, including CAMs, have nudged the southern periphery of the
Moderate Risk a tad farther south across eastern MO and southern
IL-IN. A bit of a messy setup ahead of the front, with multiple
meso-convective enhanced shortwaves embedded within the broader
upper trough. Because of this, expect a multi-modal heavy rainfall
footprint north-south when all is said and done. That said,
forecast confidence in deciphering such deterministic details at
this stage given the convective component is low, and as a result
for now it's probably best to defer to later shifts with tightening
up the Moderate Risk area.

Otherwise, the trends support a small southeast shift in the Slight
Risk over the Northern Plains (SD-northeast NE). Lastly, based on
the antecedent soils and likelihood of additional activity
associated along a lingering vort lobe (enhanced by Gulf breezes),
have also expanded the Marginal Risk area to the Middle-Upper TX
Coast to portions of the central Gulf Coast.

Hurley

Original discussion below..

...Northern Missouri through central Illinois and Indiana...

By the start of the day 2 forecast period a potent shortwave and
related surface low/MCV are expected to eject eastward out of the
central Plains into the Midwest. There still remains at least some
uncertainty regarding the speed and latitude of these features
(NAM3k a northern outlier for example), but PWs and IVT above the
90th climatological percentile (per the 00z GEFS) overlapping with
soils likely still recovering from recent heavy rain in the Midwest
will likely lead to a swath of scattered flash flooding. A MDT
risk was introduced with the latest outlook, spanning from MO to
central IN. Heavy rain near a strengthening surface low and
increased lift along an eastward stretching warm front across the
Ohio Valley will overlap with saturated soils and swollen rivers
across much of IL and IN. This will be one axis for potentially
widespread flash flooding, with another axis lingering across
southwest MO into eastern KS and possibly a relative minimum in
between (right now most likely centered around central to
southeast MO). This MO/KS potential is associated with the
southwestern tail of an expected MCS, where flow may become
parallel to the outflow boundary/front and promote both training
thunderstorms and redevelopment of storms by Sunday evening.
NBM probabilities for at least 2" remain very high (between
70-90%) and cover much of northern MO, central IL, and central IN.
Locally higher totals (CAMs depict potential for 4-7" totals) are
likely given the convective environment. 00Z HREF and 18Z REFS
probabilities for exceeding 3-hr FFG are around 30-60% across IL
and IN, where antecedent ground conditions are wettest. The
progressive nature of these storms may end up limiting the severity
of flash flood impacts, but coverage of flash flooding impacts is
expected to be widespread enough in the Midwest/Ohio Valley to
warrant the level 3/4 MDT risk upgrade.

...Eastern Kansas to Southwest Missouri...
More information regarding the southern end of the Saturday night
thunderstorm complex/MCS likely to sink southeastward near a
trailing cold front and impact areas near the Ozarks Sunday. 850 mb
flow is expected to become quite convergent extending from central
KS to southern MO, which will likely be the focus for training
convection potential early on and then reforming activity later in
Sunday associated with additional shortwave activity moving
eastward across the Plains. However, there is some uncertainty
surrounding if this boundary can sink further south during the day
and keep storms somewhat progressive. This all combines for
guidance to currently depict current QPF amounts of 3-4" and an
average localized max of 6". This area also includes soils
saturated due to a recent wet weather pattern, with NASA SPoRT-LIS
depicting pockets above the 80th percentile in the 0-40cm soil
moisture layer. Lastly, 00Z REFS and HREF probabilities are
agreeable with 40-70% values for exceeding 3" per 6-hrs.
Snell
=20

Day 3
Valid 12Z Mon Jun 22 2026 - 12Z Tue Jun 23 2026

...THERE IS A SLIGHT RISK IN EFFECT FROM THE OHIO VALLEY TO
SOUTHERN PLAINS...

...2000 UTC Update....

The notable change made to the Day 3 ERO was to expand the Slight
Risk. The main driver was the favorable deep-layer moisture
profiles per the latest guidance, effectively shifting the axis of
2-2.25" PWATs into the Mid Atlantic and southern New England.
Instability at this point appears lacking, however in similar
patterns (per the ERO first guess fields) highly-efficient rainfall
rates in late June will more likely lead to more issues (perhaps
more than just isolated) across the urban corridors and other areas
susceptible to flash flooding. At this point, the EFI per last
night's 00Z ECMWF is around 0.8, which along with PWATs near 2
standard deviations above normal, would certainly support an
upgrade to at least a low-end Slight Risk over these areas (at
least 15% 40km neighborhood probability).

Hurley
Original discussion below..
Day 3 continues to be an active pattern through a good portion of
the CONUS, east of the Mississippi with a progressive trough axis
pushing through the Great Lakes and Northeast leading to periods of
moderate to heavy rainfall from the Ohio Valley into the Mid
Atlantic and Northeast. Areas of the Northeast are subject to
thunderstorm prospects with the best chance for flash flooding
likely to occur in the urban footprint from Philadelphia up to
Boston with an expansion inland to the Hudson Valley down through
eastern PA. Current probs off the latest ensembles and National
Blend indicate a large zone of 30-50% probs for >2" across the
aforementioned area above with deterministic outputs closer to
2-3.5" into parts of Southern New England. MRGL risk inherited
remains in effect, but there's potential here for an upgrade as we
move closer to the D2 window, but want to see more of the CAMs to
make that decision. Limiting factor here remains low instability
and while there is a window for heavier rates to linger for 3 to 6
hours, the system overall is progressive. Some uncertainty also
exists south of central NJ along the eastern Mid-Atlantic regarding
overall coverage of thunderstorms.
Across the Southern U.S., heavy precipitation will preclude another
round of convection forming along a quasi-stationary front draped
from the Southern High Plains to the Southeastern CONUS. Probs for

1" are highest in-of the areas of Eastern OK into the Lower

Mississippi and southwestern Tennessee Valleys. Elevated theta_E's
and PWAT anomalies +2 dev. or greater indicate a formidable
environment capable of continued heavy rain potential that will
likely produce rainfall of 2-4", at least in some of the
thunderstorm activity that develops. The focal point along the
front will likely be where the heaviest rain will occur, or at
least be a low-level convergence mechanism that can enhance
regional convection. There's high enough confidence in the location
of convection for the D3 period to overlap with areas that will
have seen several inches the periods prior which led to a level 2/4
SLGT risk positioned over portions of the Southern Plains through
parts of the Lower Mississippi and neighboring Tennessee. The risk
extends through the Smokey Mountains up into parts of the Central
Appalachians in eastern KY up into WV as the convergence regime
follows the frontal positioning over these areas. Greatest chances
for multiple rounds of slow-moving thunderstorms capable of 2"+
hourly rainfall rates currently appears to be over southeast OK
into central AR and will be monitored closely once CAMs are within
range of the forecast time period.
Snell
=20

Day 4 and Day 5
Valid 12Z Tue Jun 23 2026 - 12Z Thu Jun 25 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FROM PORTIONS OF
THE CENTRAL AND SOUTHERN PLAINS, LOWER MISSISSIPPI VALLEY, AND
SOUTHEASTERN U.S ON BOTH TUESDAY AND WEDNESDAY...

2030Z Excessive Rainfall Discussion Update...
Overall...changes were pretty minimal and were done mainly to
expand the coverage of the outlook area given placement/spread of
QPF in spaghetti plots. Synoptically, the pattern evolution is
comparable to the previous discussion.

Bann

Previous Excessive Rainfall Outlook...
Day 4 is a transition period into a more typical summertime regime
for the CONUS with a longwave trough over the Northern U.S. and a
dome of mid and upper ridging orienting itself across the
southwestern CONUS. Positioning of the trough/ridge pattern will
cause a persistent northwesterly flow within the mid and upper
levels across the Central and Southern High Plains over into the
Lower Mississippi Valley as progressive shortwave pulses eject out
of the Rockies and ride the prevailing northwesterlies in place
between the ridge and trough. This highlights potential for MCS
development and flash flooding scenarios from the Front Range and
points southeast as the steering flow orients between the base of
the trough and the northeastern flank of the ridge. This is
historically projecting a case of thunderstorm maturation and
upscale growth over the area between CO/KS down through OK/TX with
potentially the Red River Basin as a focus for thunderstorm
activity. Eventually, this ends up migrating into the ArkLaTex
and/or Lower Mississippi area which is showing up in the QPF
footprint on ensembles. There has been little variance in the
recent global ensemble suite with the deterministic output also
showing very similar outcomes, at varying magnitudes with the
synoptic evolution generally stable with run-to-run continuity. The
entire setup continues through Day 5, as well, with repetition in
the mid and upper pattern as multiple vorticity maxima slide out of
the Central Rockies and migrate east-southeast through the mean
flow between the trough and ridge setup.
QPF distribution for both days is relatively even, however the D4
period is currently the most aggressive in terms of precipitation
magnitudes depicted as the time frame notes a stronger mid-level
disturbance ejecting out of the Front Range with heavy rain
prospects spanning from southwestern NE down through KS/OK,
eventually into the Lower Mississippi Valley as you work through
the end of D4 into D5. PQPF signatures for >1" of precipitation are
already pushing above 40% at lead for much of the aforementioned
area, a testament to a stable signal for widespread moderate to
heavy rain prospects as both the thermodynamic and kinematic
evolutions remain favorable for the D4 and D5 periods. Expectation
is for eventual upgrades across portions of the outlined area as we
move closer, especially if the signal remains stable and the hi-res deterministic begin outlining the higher rate characteristics for
the precipitation. Greatest risk for an upgrade is likely to occur
where there will be multiple days of convective overlap allowing
for falling FFG's and more susceptible hydrologic impacts as
regional streams and rivers become more prone to flooding. This is
a scenario where we'll be monitoring the evolution closely as more
appreciable impacts are plausible in this synoptic scale
persistence.
Kleebauer
=20

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!7Qd1lx_QVNSTnx_dVpCL5Mxe6sj9kHxYE-NPT4MAIuqI= NHKufQdAE2big5HaLdltCJCEl0CAHEC4mdUuKRoethYlwTs$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!7Qd1lx_QVNSTnx_dVpCL5Mxe6sj9kHxYE-NPT4MAIuqI= NHKufQdAE2big5HaLdltCJCEl0CAHEC4mdUuKRoetuE_mgw$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!7Qd1lx_QVNSTnx_dVpCL5Mxe6sj9kHxYE-NPT4MAIuqI= NHKufQdAE2big5HaLdltCJCEl0CAHEC4mdUuKRoeSOmc9cg$=20



$$

=3D =3D =3D
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--- SBBSecho 3.28-Linux
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FOUS30 KWBC 210052
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
852 PM EDT Sat Jun 20 2026

Day 1
Valid 01Z Sun Jun 21 2026 - 12Z Sun Jun 21 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL IN EFFECT FOR
PARTS OF THE CENTRAL PLAINS AND LOWER MISSOURI VALLEY...

01Z Update...
Only minor adjustments to the outlook area in the Plains/Lower
Missouri Valley. Numerical guidance continuity was good and radar
showed storms beginning upscale growth in roughly the right place
across the western outlook area. Not overly concerned about
excessive amounts from the warm advection rainfall about ready to
move out of the eastern portion of the outlook. More significant
changes were made along from South Texas along the gulf coast into
portions of Georgia and northern Florida. Additional convection in
the guidance later tonight precluded removing the Slight risk
along the Texas coast into Louisiana...while on-going convection
with locally heavy rainfall rates precluded removal of the Slight
Risk there even though the expectation was for weakening and
dissipation during the late-evening.

Bann

...Central Plains and Missouri Valley...

A large area of heavy rain associated with a developing MCS
starting this evening and continuing into early Sunday is expected
to bring widespread heavy rainfall and flash flooding across
portions of the central Plains into the Missouri Valley. The
greatest threat for numerous instances of flash flooding currently
is expected across southeastern Nebraska, northeastern Kansas, and
far northwestern Missouri/southwestern Iowa. Storms are expected
to initiate Saturday afternoon with peak heating over the central
High Plains and ahead of a racing shortwave crossing the Rockies.
Meanwhile, a LLJ of southeasterly flow will increase WAA and pump
deep Gulf moisture up the Plains through the day. This will force
the dryline to race eastward in response. The warm front associated
with the low and the dry line will uplift the deep moisture,
resulting in widespread shower and thunderstorm development across
Nebraska as early as this afternoon. These storms are expected to
grow upscale into an expansive, organized convective system into
the evening and overnight hours that will then track southeasterly
across the risk area.

The latest deterministic guidance shows areal average rainfall
totals along the expected path of the MCS in the 2-4" range with
locally higher amounts of 4-6", more than sufficient to lead to
potentially widespread flash flooding, which has prompted the
level 3/4 Moderate Risk. As is usually the case with convective
systems the exact path and duration will be determined by more
mesoscale details than the guidance can typically pin down. Some
CAMs (like the NAM3k) favor the northern axis of heavy rain across
southeast Nebraska closer to the developing surface low/MCV,
whereas the 00z RRFS favors a southern solution and heaviest
rainfall across central Kansas. Regardless, PWs surging to 2" by
tonight and increased forcing will support rainfall rates within
thunderstorms to be intense and around 2-3"/hr. These rates could
be exacerbated by cell mergers and brief training to quickly lead
to flash flooding concerns. The 00Z REFS and HREF both highlight
neighborhood probabilities of 3" per 6-hrs (above local FFG) around
40-50%+ within the MDT through 12Z Sun and then extending into the
=20

Day 2
Valid 12Z Sun Jun 21 2026 - 12Z Mon Jun 22 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL IN EFFECT FOR
PARTS OF THE CENTRAL PLAINS, MIDDLE MISSISSIPPI VALLEY, AND OHIO
VALLEY...

...2000 UTC update...

For the most part, the outlook areas on Day 2 are largely intact.
Based on the latest (12Z) suite of deterministic and probabilistic
guidance, including CAMs, have nudged the southern periphery of the
Moderate Risk a tad farther south across eastern MO and southern
IL-IN. A bit of a messy setup ahead of the front, with multiple
meso-convective enhanced shortwaves embedded within the broader
upper trough. Because of this, expect a multi-modal heavy rainfall
footprint north-south when all is said and done. That said,
forecast confidence in deciphering such deterministic details at
this stage given the convective component is low, and as a result
for now it's probably best to defer to later shifts with tightening
up the Moderate Risk area.

Otherwise, the trends support a small southeast shift in the Slight
Risk over the Northern Plains (SD-northeast NE). Lastly, based on
the antecedent soils and likelihood of additional activity
associated along a lingering vort lobe (enhanced by Gulf breezes),
have also expanded the Marginal Risk area to the Middle-Upper TX
Coast to portions of the central Gulf Coast.

Hurley
Original discussion below..
...Northern Missouri through central Illinois and Indiana...
By the start of the day 2 forecast period a potent shortwave and
related surface low/MCV are expected to eject eastward out of the
central Plains into the Midwest. There still remains at least some
uncertainty regarding the speed and latitude of these features
(NAM3k a northern outlier for example), but PWs and IVT above the
90th climatological percentile (per the 00z GEFS) overlapping with
soils likely still recovering from recent heavy rain in the Midwest
will likely lead to a swath of scattered flash flooding. A MDT
risk was introduced with the latest outlook, spanning from MO to
central IN. Heavy rain near a strengthening surface low and
increased lift along an eastward stretching warm front across the
Ohio Valley will overlap with saturated soils and swollen rivers
across much of IL and IN. This will be one axis for potentially
widespread flash flooding, with another axis lingering across
southwest MO into eastern KS and possibly a relative minimum in
between (right now most likely centered around central to
southeast MO). This MO/KS potential is associated with the
southwestern tail of an expected MCS, where flow may become
parallel to the outflow boundary/front and promote both training
thunderstorms and redevelopment of storms by Sunday evening.
NBM probabilities for at least 2" remain very high (between
70-90%) and cover much of northern MO, central IL, and central IN.
Locally higher totals (CAMs depict potential for 4-7" totals) are
likely given the convective environment. 00Z HREF and 18Z REFS
probabilities for exceeding 3-hr FFG are around 30-60% across IL
and IN, where antecedent ground conditions are wettest. The
progressive nature of these storms may end up limiting the severity
of flash flood impacts, but coverage of flash flooding impacts is
expected to be widespread enough in the Midwest/Ohio Valley to
warrant the level 3/4 MDT risk upgrade.
...Eastern Kansas to Southwest Missouri...
More information regarding the southern end of the Saturday night
thunderstorm complex/MCS likely to sink southeastward near a
trailing cold front and impact areas near the Ozarks Sunday. 850 mb
flow is expected to become quite convergent extending from central
KS to southern MO, which will likely be the focus for training
convection potential early on and then reforming activity later in
Sunday associated with additional shortwave activity moving
eastward across the Plains. However, there is some uncertainty
surrounding if this boundary can sink further south during the day
and keep storms somewhat progressive. This all combines for
guidance to currently depict current QPF amounts of 3-4" and an
average localized max of 6". This area also includes soils
saturated due to a recent wet weather pattern, with NASA SPoRT-LIS
depicting pockets above the 80th percentile in the 0-40cm soil
moisture layer. Lastly, 00Z REFS and HREF probabilities are
agreeable with 40-70% values for exceeding 3" per 6-hrs.
Snell
=20

Day 3
Valid 12Z Mon Jun 22 2026 - 12Z Tue Jun 23 2026

...THERE IS A SLIGHT RISK IN EFFECT FROM THE OHIO VALLEY TO
SOUTHERN PLAINS...

...2000 UTC Update....

The notable change made to the Day 3 ERO was to expand the Slight
Risk. The main driver was the favorable deep-layer moisture
profiles per the latest guidance, effectively shifting the axis of
2-2.25" PWATs into the Mid Atlantic and southern New England.
Instability at this point appears lacking, however in similar
patterns (per the ERO first guess fields) highly-efficient rainfall
rates in late June will more likely lead to more issues (perhaps
more than just isolated) across the urban corridors and other areas
susceptible to flash flooding. At this point, the EFI per last
night's 00Z ECMWF is around 0.8, which along with PWATs near 2
standard deviations above normal, would certainly support an
upgrade to at least a low-end Slight Risk over these areas (at
least 15% 40km neighborhood probability).

Hurley
Original discussion below..
Day 3 continues to be an active pattern through a good portion of
the CONUS, east of the Mississippi with a progressive trough axis
pushing through the Great Lakes and Northeast leading to periods of
moderate to heavy rainfall from the Ohio Valley into the Mid
Atlantic and Northeast. Areas of the Northeast are subject to
thunderstorm prospects with the best chance for flash flooding
likely to occur in the urban footprint from Philadelphia up to
Boston with an expansion inland to the Hudson Valley down through
eastern PA. Current probs off the latest ensembles and National
Blend indicate a large zone of 30-50% probs for >2" across the
aforementioned area above with deterministic outputs closer to
2-3.5" into parts of Southern New England. MRGL risk inherited
remains in effect, but there's potential here for an upgrade as we
move closer to the D2 window, but want to see more of the CAMs to
make that decision. Limiting factor here remains low instability
and while there is a window for heavier rates to linger for 3 to 6
hours, the system overall is progressive. Some uncertainty also
exists south of central NJ along the eastern Mid-Atlantic regarding
overall coverage of thunderstorms.
Across the Southern U.S., heavy precipitation will preclude another
round of convection forming along a quasi-stationary front draped
from the Southern High Plains to the Southeastern CONUS. Probs for

1" are highest in-of the areas of Eastern OK into the Lower

Mississippi and southwestern Tennessee Valleys. Elevated theta_E's
and PWAT anomalies +2 dev. or greater indicate a formidable
environment capable of continued heavy rain potential that will
likely produce rainfall of 2-4", at least in some of the
thunderstorm activity that develops. The focal point along the
front will likely be where the heaviest rain will occur, or at
least be a low-level convergence mechanism that can enhance
regional convection. There's high enough confidence in the location
of convection for the D3 period to overlap with areas that will
have seen several inches the periods prior which led to a level 2/4
SLGT risk positioned over portions of the Southern Plains through
parts of the Lower Mississippi and neighboring Tennessee. The risk
extends through the Smokey Mountains up into parts of the Central
Appalachians in eastern KY up into WV as the convergence regime
follows the frontal positioning over these areas. Greatest chances
for multiple rounds of slow-moving thunderstorms capable of 2"+
hourly rainfall rates currently appears to be over southeast OK
into central AR and will be monitored closely once CAMs are within
range of the forecast time period.
Snell
=20

Day 4 and Day 5
Valid 12Z Tue Jun 23 2026 - 12Z Thu Jun 25 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FROM PORTIONS OF
THE CENTRAL AND SOUTHERN PLAINS, LOWER MISSISSIPPI VALLEY, AND
SOUTHEASTERN U.S ON BOTH TUESDAY AND WEDNESDAY...

2030Z Excessive Rainfall Discussion Update...
Overall...changes were pretty minimal and were done mainly to
expand the coverage of the outlook area given placement/spread of
QPF in spaghetti plots. Synoptically, the pattern evolution is
comparable to the previous discussion.

Bann


Previous Excessive Rainfall Outlook...
Day 4 is a transition period into a more typical summertime regime
for the CONUS with a longwave trough over the Northern U.S. and a
dome of mid and upper ridging orienting itself across the
southwestern CONUS. Positioning of the trough/ridge pattern will
cause a persistent northwesterly flow within the mid and upper
levels across the Central and Southern High Plains over into the
Lower Mississippi Valley as progressive shortwave pulses eject out
of the Rockies and ride the prevailing northwesterlies in place
between the ridge and trough. This highlights potential for MCS
development and flash flooding scenarios from the Front Range and
points southeast as the steering flow orients between the base of
the trough and the northeastern flank of the ridge. This is
historically projecting a case of thunderstorm maturation and
upscale growth over the area between CO/KS down through OK/TX with
potentially the Red River Basin as a focus for thunderstorm
activity. Eventually, this ends up migrating into the ArkLaTex
and/or Lower Mississippi area which is showing up in the QPF
footprint on ensembles. There has been little variance in the
recent global ensemble suite with the deterministic output also
showing very similar outcomes, at varying magnitudes with the
synoptic evolution generally stable with run-to-run continuity. The
entire setup continues through Day 5, as well, with repetition in
the mid and upper pattern as multiple vorticity maxima slide out of
the Central Rockies and migrate east-southeast through the mean
flow between the trough and ridge setup.
QPF distribution for both days is relatively even, however the D4
period is currently the most aggressive in terms of precipitation
magnitudes depicted as the time frame notes a stronger mid-level
disturbance ejecting out of the Front Range with heavy rain
prospects spanning from southwestern NE down through KS/OK,
eventually into the Lower Mississippi Valley as you work through
the end of D4 into D5. PQPF signatures for >1" of precipitation are
already pushing above 40% at lead for much of the aforementioned
area, a testament to a stable signal for widespread moderate to
heavy rain prospects as both the thermodynamic and kinematic
evolutions remain favorable for the D4 and D5 periods. Expectation
is for eventual upgrades across portions of the outlined area as we
move closer, especially if the signal remains stable and the hi-res deterministic begin outlining the higher rate characteristics for
the precipitation. Greatest risk for an upgrade is likely to occur
where there will be multiple days of convective overlap allowing
for falling FFG's and more susceptible hydrologic impacts as
regional streams and rivers become more prone to flooding. This is
a scenario where we'll be monitoring the evolution closely as more
appreciable impacts are plausible in this synoptic scale
persistence.
Kleebauer
=20

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!-MP4X75MXtuGMTSVBrcE8xh8FfqSJViRZkVZg1CIN774= xiX-Zk0k6Sqkcu9A7h2w0NLMk40U6-96BwdkD7NlZxL7ff0$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!-MP4X75MXtuGMTSVBrcE8xh8FfqSJViRZkVZg1CIN774= xiX-Zk0k6Sqkcu9A7h2w0NLMk40U6-96BwdkD7Nl8E9TeVA$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!-MP4X75MXtuGMTSVBrcE8xh8FfqSJViRZkVZg1CIN774= xiX-Zk0k6Sqkcu9A7h2w0NLMk40U6-96BwdkD7Nllj-hpH4$=20



$$

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FOUS30 KWBC 210749
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
349 AM EDT Sun Jun 21 2026

Day 1
Valid 12Z Sun Jun 21 2026 - 12Z Mon Jun 22 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL IN EFFECT FOR
PARTS OF THE CENTRAL PLAINS, MIDDLE MISSISSIPPI VALLEY, AND OHIO
VALLEY...

...Northern Missouri through central Illinois and Indiana...

By the start of the day 1 forecast period a potent shortwave and
related surface low/MCV are expected to eject eastward out of the
central Plains into the Midwest, driving the flash flood threat
today from Kansas to Indiana. The regional radar representation
early this morning over the central Plains is complex, with several
clusters of thunderstorms and a trailing stationary axis of heavy
rainfall across northwest Kansas. The expectation for the start of
this day 1 outlook (12Z Sat) is for these thunderstorms to organize
into a larger MCS spanning from northern MO to south-central KS.
However, compared to normal forecasts within 12 hours, there
remains some uncertainty with respect to the location of the
heaviest rainfall. However, scattered instances of flash flooding
are still expected within the MDT risk and locally significant
flash flooding impacts cannot be ruled out.

00Z CAMs and radar were utilized to define the western edge of the
SLGT and MDT risk areas and to highlight training potential over
south- central and southeast KS at the start of the forecast
period. Another axis of heavy rainfall is possible this morning and
through the day into the Midwest near the lifting warm front and
surface low/MCV. PWs and IVT above the 90th climatological
percentile (per the 00z GEFS) overlapping with soils likely still
recovering from recent heavy rain in the Midwest will lead to a
swath of at least scattered flash flooding. Antecedent ground
conditions are likely to exacerbate flash flooding where 2"/hr
rainfall rates occur, especially across parts of central IL and
central IN, where NASA SPoRT-LIS 40 cm soil moisture is above the
80th percentile and rivers remain swollen from previous rainfall
over the last week. 00z HREF and REFS neighborhood probabilities
for at least 3" per 6-hrs are between 30-50% across northern MO to
central IL and southern IN, which would exceed local FFG. While the
overall system will remain fairly progressive, flow oriented
parallel to the trailing front/outflow boundary could prompt
thunderstorm redevelopment late this afternoon and evening
extending from central MO to southern IN and northern KY. This
potential for repeating storms allowed for the MDT to shift a bit
south with this update and adds additional potential for locally
severe flash flooding.

...Southeast Kansas to Southwest Missouri...

The southwestern flank of the ongoing MCS this morning is expected
to extend from south-central KS to southwest MO as 850 mb flow is
expected to become quite convergent. This may also become a focus
for reforming activity later tonight associated with additional
shortwave activity moving eastward across the Plains. However,
there is some uncertainty surrounding if this boundary can sink
further south during the day and keep storms somewhat progressive
or situated over OK and AR instead. Regardless, this all combines
for guidance to currently depict current QPF amounts of 3-4" and an
average localized max of 6". Parts of southwest MO have saturated
antecedent ground conditions due to a recent wet weather pattern,
with NASA SPoRT-LIS depicting pockets above the 80th percentile in
the 0-40cm soil moisture layer. Lastly, 00Z REFS and HREF
probabilities are agreeable with 20-60% values for exceeding 3" per
6-hrs between the two potential rounds, though may be underdone
across south-central and southeast KS for this morning's activity
based on radar and HRRR/RRFS trends.

...Upper/Middle Texas Gulf Coast to Southwest Louisiana...

A very moist atmosphere remains in place along with an upper low
over South Texas to help foster additional heavy rainfall chances,
primarily this morning, across the middle TX coast to southwest
LA. A remnant outflow boundary located in the northwest Gulf this
morning is expected to lift northward as return flow increases and
spark convection early this morning. PWs over 2.4" will allow for
any thunderstorms to contain 2-3"/hr rates and may linger in a
localized manner over similar locations and cause isolated to
scattered flash flooding. This area remains overly saturated from
prior torrential rains the last few days, which increases the
concern somewhat for additional flash flooding impacts today and
thus the addition of a SLGT risk in the excessive rainfall outlook.

...South Dakota...

Previously outlooked SLGT risk was removed with this update as the
slow-moving upper low produces scattered meandering thunderstorms,
but coverage is not expected to be enough for more than isolated
flash flooding in an area with fairly dry antecedent ground
conditions. Still, isolated flash flooding is possible and supports
the MRGL risk designation.

...Southern Mississippi, Alabama, and the Florida Panhandle...

Additional scattered thunderstorms are likely for the central Gulf
Coast states and Florida Panhandle, an area that has experienced
rounds of extreme rainfall over the last several days. A MRGL risk
remains in effect today, which highlights the potential for
isolated flash flooding. Thunderstorms are expected to remain
widely scattered as a front lifts well north towards the southern
Appalachians today. Thus, limited focus for storms to remain over
one area for enough duration to produce more than 3-4" of rain and
expectation that a MRGL will suffice even though FFG remains
drastically lower than normal for this part of the country. As
always, urban areas will be most susceptible to flash flooding
impacts should storms set up directly overhead and linger given the
moist southwesterly flow in place.

Snell
=20

Day 2
Valid 12Z Mon Jun 22 2026 - 12Z Tue Jun 23 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL IN EFFECT FROM THE
SOUTHERN PLAINS TO THE NORTHEAST...

...Northeast and Mid-Atlantic...

The day 2 forecast period will feature a progressive trough axis
pushing from the Great Lakes to the Northeast with a trailing
frontal boundary reach southwest to the Southern Plains and above
average PWs along the axis to help create excessive rainfall
concerns. Areas of the Northeast and I-95 corridor as south as
Washington D.C. are subject to thunderstorm prospects with the
best chance for flash flooding likely to occur in the urban
footprint from D.C. to NYC with an expansion inland to central PA.
Current probs off the latest ensembles and National Blend indicate
a large zone of 30-50% probs for >2" across the aforementioned
area above with deterministic outputs closer to 2-3.5" into parts
of Southern New England. The 00z HREF (only covers through 00Z
6/23) and 00Z REFS indicate 30-60% neighborhood probabilities for
at least 2" per 6-hrs from D.C. to NYC and would be enough for
some urban flash flooding concerns. There has been additional
uncertainty farther north and east with how far to extend the SLGT
risk, but given typical mesoscale uncertainties and limited
instability, in coordination with local forecast offices the SLGT
risk was confined a bit. Look for additional refinements once the
full suite of CAMs is available, especially with increasing PWs
near the 90th climatological percentile and a nearby warm front in
the area for potential focused axis for thunderstorms.

...Southern Plains to Central Appalachians...

Across the Southern U.S., heavy precipitation will preclude
another round of convection forming along a quasi-stationary front
draped from the Southern High Plains to the Southeastern CONUS.
Probs for >1" are highest in-of the areas of Eastern OK into the
Lower Mississippi and southwestern Tennessee Valleys. Elevated
theta_E's and PWAT anomalies +2 dev. or greater indicate a
formidable environment capable of continued heavy rain potential
that will likely produce rainfall of 2-4", at least in some of the
thunderstorm activity that develops. The focal point along the
front will likely be where the heaviest rain will occur, or at
least be a low-level convergence mechanism that can enhance
regional convection. There's high enough confidence in the location
of convection for the D2 period to overlap with areas that will
have seen several inches the periods prior which led to a level 2/4
SLGT risk positioned over portions of the Southern Plains through
parts of the Southern Plains, Lower Mississippi Valley and
neighboring Tennessee Valley. The risk extends through the Smokey
Mountains up into parts of the Central Appalachians in eastern KY
up into WV as the convergence regime follows the frontal
positioning over these areas. Greatest chances for multiple rounds
of slow-moving thunderstorms capable of 2"+ hourly rainfall rates
currently appears to be over southeast OK into central AR and will
be monitored closely once CAMs are within range of the forecast
time period. Latest "longer range" REFS and HREF probabilities for
at least 3" are scattered throughout the region.

Snell
=20

Day 3
Valid 12Z Tue Jun 23 2026 - 12Z Wed Jun 24 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL IN EFFECT FROM
PARTS OF THE CENTRAL PLAINS TO THE SOUTHEAST...

...Central Plains to Southeast...

Day 3 is a transition period into a more typical summertime regime
for the CONUS with a longwave trough over the Northern U.S. and a
dome of mid and upper ridging orienting itself across the
southwestern CONUS. Positioning of the trough/ridge pattern will
cause a persistent northwesterly flow within the mid and upper
levels across the Central and Southern High Plains over into the
Lower Mississippi Valley as progressive shortwave pulses eject out
of the Rockies and ride the prevailing northwesterlies in place
between the ridge and trough. This highlights potential for MCS
development and flash flooding scenarios from the Front Range and
points southeast as the steering flow orients between the base of
the trough and the northeastern flank of the ridge. This is
historically projecting a case of thunderstorm maturation and
upscale growth over the area between CO/KS down through OK/TX with
potentially the Red River Basin as a focus for thunderstorm
activity. Eventually, this ends up migrating into the ArkLaTex
and/or Lower Mississippi area which is showing up in the QPF
footprint on ensembles. There has been little variance in the
recent global ensemble suite with the deterministic output also
showing very similar outcomes, at varying magnitudes with the
synoptic evolution generally stable with run-to-run continuity.
Should CAMs come into better focus for aforementioned MCS activity
over the region, a SLGT risk could be introduced in future updates.

Snell
=20

Day 4 and Day 5

Valid 12Z Wed Jun 24 2026 - 12Z Fri Jun 26 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FROM PORTIONS OF
THE CENTRAL AND SOUTHERN PLAINS, LOWER MISSISSIPPI VALLEY, AND
SOUTHEASTERN U.S ON BOTH WEDNESDAY AND THURSDAY...

Both the D4 and D5 time frames remain in a more typical summertime
regime for the CONUS with a longwave trough over the Northern U.S.
and a dome of mid and upper ridging orienting itself across the
southwestern CONUS. Positioning of the trough/ridge pattern will
allow for persistent northwesterly flow within the mid and upper
levels across the Central and Southern High Plains over into the
Lower Mississippi Valley as progressive shortwave pulses eject out
of the Rockies and ride the prevailing northwesterlies in place
between the ridge and trough. Global deterministic and their
ensembles continue to depict a setup conducive for scattered to
widespread convective activity with general organization likely to
occur over the course of each evening as thunderstorms grow
upstream and migrate southeast within the prevailing
northwesterlies between 700-300mb. Moisture and instability will
remain elevated across much of the aforementioned areas with the
latest NAEFS output signaling a northwest to southeast alignment of
PWAT anomalies between +1 to +2 standard deviations from the WY
Front Range down to the ArkLaTex. This is historically projecting
a case of thunderstorm maturation and upscale growth over the area
outlined within the anomaly field with a correlation of a defined
theta_E ridge focused within that same zone. This would allow for
convective initiation upstream over the Front Range with organized
convective evolutions to drawn southeastward along the theta_E
gradient and oriented with the mean flow aloft. This would likely
entail convection motioning into KS/OK and pivoting eastward
towards the ArkLaTex as progs indicate the positioning of a quasi-
stationary front situated across the Lower Mississippi Valley which
would turn to a focal point for convection. ML outputs are a bit
further south with the potential as the EC-AIFS Ensemble even
promotes the threat for heavy convection towards the Red River
Basin, so there is some opportunity for southern adjustments in the
mean QPF as we move closer, so long as that signal remains stable
in the means. Overall, there has been little variance in the
recent global ensemble suite with the deterministic output also
showing very similar outcomes, at varying magnitudes with the
synoptic evolution generally stable with run- to-run continuity.

The entire setup continues through Day 5, as well, with repetition
in the mid and upper pattern as multiple vorticity maxima slide out
of the Central Rockies and migrate east- southeast through the
mean flow between the trough and ridge setup. There is now some
indication the ridging breaks down as a the heights across the west
get squashed in favor of a much stronger upper trough migrating out
of the northeastern Pacific into the Pacific Northwest and Northern
Rockies. The signal is showing up within the 500mb Height Anomalies
on both the ECENS and GEFS, a solid consensus in the pattern
breaking down somewhat as we move into the end of the week. This
will likely signal an end to the persistent northwesterlies after
the D5 window, however strong shortwave ejections will still be
plausible, as noted via the D5 window where there's growing favor
for heavy precip to occur across much of the Central Plains during
the period Thursday and Thursday night. Greatest probabilities
within the >1" PQPF are situated over southwestern NE down through
KS into OK with a general 25-50% already showing up across the
region. For a convective pattern at 5-day leads, this is a
relatively formidable signal in the threat for heavy rainfall, so
both the D4 and D5 time frames are likely going to see some short
term forecast upgrades as we gain further consensus in the
deterministic, especially as we step into the range of the CAMs.
PQPF for >2" over 72hrs (D3-5) is between 30-60% across the
ArkLaTex into the Lower Mississippi area of southern AR. This is
the most likely location for an upgrade in the risk, especially as
the recent NBM continues to pin this area as the focal point for
overlapping convection in the D3-5 window. MRGL risks remain the
forecast for both the D4 and D5 periods for the time being.

Kleebauer
=20

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!75ZSMvMHKBtqhueC1RVdfqzd3NxYLoxHqaGYMzdp1rx4= WZ3wsceajOS_dZDjAcwuawliFZ-rQQCwYGCEHgVGK6LFaRI$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!75ZSMvMHKBtqhueC1RVdfqzd3NxYLoxHqaGYMzdp1rx4= WZ3wsceajOS_dZDjAcwuawliFZ-rQQCwYGCEHgVG0d7W5nM$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!75ZSMvMHKBtqhueC1RVdfqzd3NxYLoxHqaGYMzdp1rx4= WZ3wsceajOS_dZDjAcwuawliFZ-rQQCwYGCEHgVGK-OP6es$=20



$$

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FOUS30 KWBC 211544
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1144 AM EDT Sun Jun 21 2026

Day 1
Valid 16Z Sun Jun 21 2026 - 12Z Mon Jun 22 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL IN EFFECT FOR
PARTS OF THE CENTRAL PLAINS, MIDDLE MISSISSIPPI VALLEY, AND OHIO
VALLEY...

16 UTC Update:

Current line of storms has pushed quickly through eastern Kansas
and western Missouri with well defined MCV noted. The northern
flank of this activity is expected to continue eastward into
Illinois and eventually Indiana. With diurnal heating this
afternoon, the coverage and intensity of storms will likely uptick.
While the progressive nature of this line may limit the overall
duration of any particular thunderstorm and intense rainfall, some
repeating rounds will be possible. Additionally, the wet antecedent
conditions will allow for greater runoff. All said, rainfall
amounts of 1-3" with isolated higher amounts will be possible from
eastern MO through south-central Illinois and Indiana. The key
message is that intense rain rates (locally over 2"/hr) over very
wet antecedent conditions may result in excessive runoff and
flooding, some of which could be locally significant.

Further south, the southern flank of precipitation is advancing
into northeastern OK and northwestern AR, and this activity is
likely to dissipate over the next few hours. However, it will set
up an outflow boundary and with this evening's low level jet and
another shortwave, will be the trigger for an quasi west to east
oriented line of thunderstorms. Initially, storm motions will be
slow with possible repeating/training storms. Localized 2-4" totals
with some potential for isolated higher amounts.

The main changes to the ERO was to trim the western edges of the
risk areas as the main threat of significant heavy rainfall has
lowered. The Moderate Risks were confined to eastern MO through
Indiana with the main northern shield of heavy rain with a separate
secondary area for later activity across southeast KS, southwest
MO, northeast OK, and northwest AR.

Elsewhere, minimal changes were made with some tweaks across the
Gulf Coast with the Slight Risk along the Texas Gulf Coast.

Taylor

previous discussion...

...Northern Missouri through central Illinois and Indiana...
By the start of the day 1 forecast period a potent shortwave and
related surface low/MCV are expected to eject eastward out of the
central Plains into the Midwest, driving the flash flood threat
today from Kansas to Indiana. The regional radar representation
early this morning over the central Plains is complex, with several
clusters of thunderstorms and a trailing stationary axis of heavy
rainfall across northwest Kansas. The expectation for the start of
this day 1 outlook (12Z Sat) is for these thunderstorms to organize
into a larger MCS spanning from northern MO to south-central KS.
However, compared to normal forecasts within 12 hours, there
remains some uncertainty with respect to the location of the
heaviest rainfall. However, scattered instances of flash flooding
are still expected within the MDT risk and locally significant
flash flooding impacts cannot be ruled out.

00Z CAMs and radar were utilized to define the western edge of the
SLGT and MDT risk areas and to highlight training potential over
south- central and southeast KS at the start of the forecast
period. Another axis of heavy rainfall is possible this morning and
through the day into the Midwest near the lifting warm front and
surface low/MCV. PWs and IVT above the 90th climatological
percentile (per the 00z GEFS) overlapping with soils likely still
recovering from recent heavy rain in the Midwest will lead to a
swath of at least scattered flash flooding. Antecedent ground
conditions are likely to exacerbate flash flooding where 2"/hr
rainfall rates occur, especially across parts of central IL and
central IN, where NASA SPoRT-LIS 40 cm soil moisture is above the
80th percentile and rivers remain swollen from previous rainfall
over the last week. 00z HREF and REFS neighborhood probabilities
for at least 3" per 6-hrs are between 30-50% across northern MO to
central IL and southern IN, which would exceed local FFG. While the
overall system will remain fairly progressive, flow oriented
parallel to the trailing front/outflow boundary could prompt
thunderstorm redevelopment late this afternoon and evening
extending from central MO to southern IN and northern KY. This
potential for repeating storms allowed for the MDT to shift a bit
south with this update and adds additional potential for locally
severe flash flooding.

...Southeast Kansas to Southwest Missouri...
The southwestern flank of the ongoing MCS this morning is expected
to extend from south-central KS to southwest MO as 850 mb flow is
expected to become quite convergent. This may also become a focus
for reforming activity later tonight associated with additional
shortwave activity moving eastward across the Plains. However,
there is some uncertainty surrounding if this boundary can sink
further south during the day and keep storms somewhat progressive
or situated over OK and AR instead. Regardless, this all combines
for guidance to currently depict current QPF amounts of 3-4" and an
average localized max of 6". Parts of southwest MO have saturated
antecedent ground conditions due to a recent wet weather pattern,
with NASA SPoRT-LIS depicting pockets above the 80th percentile in
the 0-40cm soil moisture layer. Lastly, 00Z REFS and HREF
probabilities are agreeable with 20-60% values for exceeding 3" per
6-hrs between the two potential rounds, though may be underdone
across south-central and southeast KS for this morning's activity
based on radar and HRRR/RRFS trends.

...Upper/Middle Texas Gulf Coast to Southwest Louisiana...
A very moist atmosphere remains in place along with an upper low
over South Texas to help foster additional heavy rainfall chances,
primarily this morning, across the middle TX coast to southwest
LA. A remnant outflow boundary located in the northwest Gulf this
morning is expected to lift northward as return flow increases and
spark convection early this morning. PWs over 2.4" will allow for
any thunderstorms to contain 2-3"/hr rates and may linger in a
localized manner over similar locations and cause isolated to
scattered flash flooding. This area remains overly saturated from
prior torrential rains the last few days, which increases the
concern somewhat for additional flash flooding impacts today and
thus the addition of a SLGT risk in the excessive rainfall outlook.

...South Dakota...
Previously outlooked SLGT risk was removed with this update as the
slow-moving upper low produces scattered meandering thunderstorms,
but coverage is not expected to be enough for more than isolated
flash flooding in an area with fairly dry antecedent ground
conditions. Still, isolated flash flooding is possible and supports
the MRGL risk designation.

...Southern Mississippi, Alabama, and the Florida Panhandle...
Additional scattered thunderstorms are likely for the central Gulf
Coast states and Florida Panhandle, an area that has experienced
rounds of extreme rainfall over the last several days. A MRGL risk
remains in effect today, which highlights the potential for
isolated flash flooding. Thunderstorms are expected to remain
widely scattered as a front lifts well north towards the southern
Appalachians today. Thus, limited focus for storms to remain over
one area for enough duration to produce more than 3-4" of rain and
expectation that a MRGL will suffice even though FFG remains
drastically lower than normal for this part of the country. As
always, urban areas will be most susceptible to flash flooding
impacts should storms set up directly overhead and linger given the
moist southwesterly flow in place.

Snell
=20

Day 2
Valid 12Z Mon Jun 22 2026 - 12Z Tue Jun 23 2026

...THERE IS A SLIGHT RISK IN EFFECT FROM THE SOUTHERN PLAINS TO THE NORTHEAST...

...Northeast and Mid-Atlantic...

The day 2 forecast period will feature a progressive trough axis
pushing from the Great Lakes to the Northeast with a trailing
frontal boundary reach southwest to the Southern Plains and above
average PWs along the axis to help create excessive rainfall
concerns. Areas of the Northeast and I-95 corridor as south as
Washington D.C. are subject to thunderstorm prospects with the
best chance for flash flooding likely to occur in the urban
footprint from D.C. to NYC with an expansion inland to central PA.
Current probs off the latest ensembles and National Blend indicate
a large zone of 30-50% probs for >2" across the aforementioned
area above with deterministic outputs closer to 2-3.5" into parts
of Southern New England. The 00z HREF (only covers through 00Z
6/23) and 00Z REFS indicate 30-60% neighborhood probabilities for
at least 2" per 6-hrs from D.C. to NYC and would be enough for
some urban flash flooding concerns. There has been additional
uncertainty farther north and east with how far to extend the SLGT
risk, but given typical mesoscale uncertainties and limited
instability, in coordination with local forecast offices the SLGT
risk was confined a bit. Look for additional refinements once the
full suite of CAMs is available, especially with increasing PWs
near the 90th climatological percentile and a nearby warm front in
the area for potential focused axis for thunderstorms.

...Southern Plains to Central Appalachians...

Across the Southern U.S., heavy precipitation will preclude
another round of convection forming along a quasi-stationary front
draped from the Southern High Plains to the Southeastern CONUS.
Probs for >1" are highest in-of the areas of Eastern OK into the
Lower Mississippi and southwestern Tennessee Valleys. Elevated
theta_E's and PWAT anomalies +2 dev. or greater indicate a
formidable environment capable of continued heavy rain potential
that will likely produce rainfall of 2-4", at least in some of the
thunderstorm activity that develops. The focal point along the
front will likely be where the heaviest rain will occur, or at
least be a low-level convergence mechanism that can enhance
regional convection. There's high enough confidence in the location
of convection for the D2 period to overlap with areas that will
have seen several inches the periods prior which led to a level 2/4
SLGT risk positioned over portions of the Southern Plains through
parts of the Southern Plains, Lower Mississippi Valley and
neighboring Tennessee Valley. The risk extends through the Smokey
Mountains up into parts of the Central Appalachians in eastern KY
up into WV as the convergence regime follows the frontal
positioning over these areas. Greatest chances for multiple rounds
of slow-moving thunderstorms capable of 2"+ hourly rainfall rates
currently appears to be over southeast OK into central AR and will
be monitored closely once CAMs are within range of the forecast
time period. Latest "longer range" REFS and HREF probabilities for
at least 3" are scattered throughout the region.

Snell
=20

Day 3
Valid 12Z Tue Jun 23 2026 - 12Z Wed Jun 24 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL IN EFFECT FROM
PARTS OF THE CENTRAL PLAINS TO THE SOUTHEAST...

...Central Plains to Southeast...

Day 3 is a transition period into a more typical summertime regime
for the CONUS with a longwave trough over the Northern U.S. and a
dome of mid and upper ridging orienting itself across the
southwestern CONUS. Positioning of the trough/ridge pattern will
cause a persistent northwesterly flow within the mid and upper
levels across the Central and Southern High Plains over into the
Lower Mississippi Valley as progressive shortwave pulses eject out
of the Rockies and ride the prevailing northwesterlies in place
between the ridge and trough. This highlights potential for MCS
development and flash flooding scenarios from the Front Range and
points southeast as the steering flow orients between the base of
the trough and the northeastern flank of the ridge. This is
historically projecting a case of thunderstorm maturation and
upscale growth over the area between CO/KS down through OK/TX with
potentially the Red River Basin as a focus for thunderstorm
activity. Eventually, this ends up migrating into the ArkLaTex
and/or Lower Mississippi area which is showing up in the QPF
footprint on ensembles. There has been little variance in the
recent global ensemble suite with the deterministic output also
showing very similar outcomes, at varying magnitudes with the
synoptic evolution generally stable with run-to-run continuity.
Should CAMs come into better focus for aforementioned MCS activity
over the region, a SLGT risk could be introduced in future updates.

Snell
=20

Day 4 and Day 5

Valid 12Z Wed Jun 24 2026 - 12Z Fri Jun 26 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FROM PORTIONS OF
THE CENTRAL AND SOUTHERN PLAINS, LOWER MISSISSIPPI VALLEY, AND
SOUTHEASTERN U.S ON BOTH WEDNESDAY AND THURSDAY...

Both the D4 and D5 time frames remain in a more typical summertime
regime for the CONUS with a longwave trough over the Northern U.S.
and a dome of mid and upper ridging orienting itself across the
southwestern CONUS. Positioning of the trough/ridge pattern will
allow for persistent northwesterly flow within the mid and upper
levels across the Central and Southern High Plains over into the
Lower Mississippi Valley as progressive shortwave pulses eject out
of the Rockies and ride the prevailing northwesterlies in place
between the ridge and trough. Global deterministic and their
ensembles continue to depict a setup conducive for scattered to
widespread convective activity with general organization likely to
occur over the course of each evening as thunderstorms grow
upstream and migrate southeast within the prevailing
northwesterlies between 700-300mb. Moisture and instability will
remain elevated across much of the aforementioned areas with the
latest NAEFS output signaling a northwest to southeast alignment of
PWAT anomalies between +1 to +2 standard deviations from the WY
Front Range down to the ArkLaTex. This is historically projecting
a case of thunderstorm maturation and upscale growth over the area
outlined within the anomaly field with a correlation of a defined
theta_E ridge focused within that same zone. This would allow for
convective initiation upstream over the Front Range with organized
convective evolutions to drawn southeastward along the theta_E
gradient and oriented with the mean flow aloft. This would likely
entail convection motioning into KS/OK and pivoting eastward
towards the ArkLaTex as progs indicate the positioning of a quasi-
stationary front situated across the Lower Mississippi Valley which
would turn to a focal point for convection. ML outputs are a bit
further south with the potential as the EC-AIFS Ensemble even
promotes the threat for heavy convection towards the Red River
Basin, so there is some opportunity for southern adjustments in the
mean QPF as we move closer, so long as that signal remains stable
in the means. Overall, there has been little variance in the
recent global ensemble suite with the deterministic output also
showing very similar outcomes, at varying magnitudes with the
synoptic evolution generally stable with run- to-run continuity.

The entire setup continues through Day 5, as well, with repetition
in the mid and upper pattern as multiple vorticity maxima slide out
of the Central Rockies and migrate east- southeast through the
mean flow between the trough and ridge setup. There is now some
indication the ridging breaks down as a the heights across the west
get squashed in favor of a much stronger upper trough migrating out
of the northeastern Pacific into the Pacific Northwest and Northern
Rockies. The signal is showing up within the 500mb Height Anomalies
on both the ECENS and GEFS, a solid consensus in the pattern
breaking down somewhat as we move into the end of the week. This
will likely signal an end to the persistent northwesterlies after
the D5 window, however strong shortwave ejections will still be
plausible, as noted via the D5 window where there's growing favor
for heavy precip to occur across much of the Central Plains during
the period Thursday and Thursday night. Greatest probabilities
within the >1" PQPF are situated over southwestern NE down through
KS into OK with a general 25-50% already showing up across the
region. For a convective pattern at 5-day leads, this is a
relatively formidable signal in the threat for heavy rainfall, so
both the D4 and D5 time frames are likely going to see some short
term forecast upgrades as we gain further consensus in the
deterministic, especially as we step into the range of the CAMs.
PQPF for >2" over 72hrs (D3-5) is between 30-60% across the
ArkLaTex into the Lower Mississippi area of southern AR. This is
the most likely location for an upgrade in the risk, especially as
the recent NBM continues to pin this area as the focal point for
overlapping convection in the D3-5 window. MRGL risks remain the
forecast for both the D4 and D5 periods for the time being.

Kleebauer
=20

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!4nKeelkc0asKpbHmS-xWupaY2DHezDdssHLmVVYtQNwG= 0DZRlxUDzsHncisuQB4jvEsNrnDX3yGSGK3yywwl6Al5NLA$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!4nKeelkc0asKpbHmS-xWupaY2DHezDdssHLmVVYtQNwG= 0DZRlxUDzsHncisuQB4jvEsNrnDX3yGSGK3yywwlnWEfVC8$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!4nKeelkc0asKpbHmS-xWupaY2DHezDdssHLmVVYtQNwG= 0DZRlxUDzsHncisuQB4jvEsNrnDX3yGSGK3yywwlv8TbUk0$=20



$$

=3D =3D =3D
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--- SBBSecho 3.28-Linux
* Origin: Capitol City Online (1:2320/107)

FOUS30 KWBC 211933
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
333 PM EDT Sun Jun 21 2026

Day 1
Valid 1925Z Sun Jun 21 2026 - 12Z Mon Jun 22 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL IN EFFECT FOR
PARTS OF THE CENTRAL PLAINS, MIDDLE MISSISSIPPI VALLEY, AND OHIO
VALLEY...

20 UTC Update:
Pulse convection across portions of New England will continue to
produce isolated intense rain rates over 1"/hr at times over the
next several hours. Isolated flash flooding will be possible given
the above normal PWs in place and possible repeating rounds of
short but intense rainfall. See WPC MPD 490 for more details.

Elsewhere, the organized convection across the TX Gulf Coast has
largely dissipated and the Slight Risk there has been removed.

Taylor

16 UTC Update:

Current line of storms has pushed quickly through eastern Kansas
and western Missouri with well defined MCV noted. The northern
flank of this activity is expected to continue eastward into
Illinois and eventually Indiana. With diurnal heating this
afternoon, the coverage and intensity of storms will likely uptick.
While the progressive nature of this line may limit the overall
duration of any particular thunderstorm and intense rainfall, some
repeating rounds will be possible. Additionally, the wet antecedent
conditions will allow for greater runoff. All said, rainfall
amounts of 1-3" with isolated higher amounts will be possible from
eastern MO through south-central Illinois and Indiana. The key
message is that intense rain rates (locally over 2"/hr) over very
wet antecedent conditions may result in excessive runoff and
flooding, some of which could be locally significant.

Further south, the southern flank of precipitation is advancing
into northeastern OK and northwestern AR, and this activity is
likely to dissipate over the next few hours. However, it will set
up an outflow boundary and with this evening's low level jet and
another shortwave, will be the trigger for an quasi west to east
oriented line of thunderstorms. Initially, storm motions will be
slow with possible repeating/training storms. Localized 2-4" totals
with some potential for isolated higher amounts.

The main changes to the ERO was to trim the western edges of the
risk areas as the main threat of significant heavy rainfall has
lowered. The Moderate Risks were confined to eastern MO through
Indiana with the main northern shield of heavy rain with a separate
secondary area for later activity across southeast KS, southwest
MO, northeast OK, and northwest AR.

Elsewhere, minimal changes were made with some tweaks across the
Gulf Coast with the Slight Risk along the Texas Gulf Coast.

Taylor

previous discussion...

...Northern Missouri through central Illinois and Indiana...
By the start of the day 1 forecast period a potent shortwave and
related surface low/MCV are expected to eject eastward out of the
central Plains into the Midwest, driving the flash flood threat
today from Kansas to Indiana. The regional radar representation
early this morning over the central Plains is complex, with several
clusters of thunderstorms and a trailing stationary axis of heavy
rainfall across northwest Kansas. The expectation for the start of
this day 1 outlook (12Z Sat) is for these thunderstorms to organize
into a larger MCS spanning from northern MO to south-central KS.
However, compared to normal forecasts within 12 hours, there
remains some uncertainty with respect to the location of the
heaviest rainfall. However, scattered instances of flash flooding
are still expected within the MDT risk and locally significant
flash flooding impacts cannot be ruled out.

00Z CAMs and radar were utilized to define the western edge of the
SLGT and MDT risk areas and to highlight training potential over
south- central and southeast KS at the start of the forecast
period. Another axis of heavy rainfall is possible this morning and
through the day into the Midwest near the lifting warm front and
surface low/MCV. PWs and IVT above the 90th climatological
percentile (per the 00z GEFS) overlapping with soils likely still
recovering from recent heavy rain in the Midwest will lead to a
swath of at least scattered flash flooding. Antecedent ground
conditions are likely to exacerbate flash flooding where 2"/hr
rainfall rates occur, especially across parts of central IL and
central IN, where NASA SPoRT-LIS 40 cm soil moisture is above the
80th percentile and rivers remain swollen from previous rainfall
over the last week. 00z HREF and REFS neighborhood probabilities
for at least 3" per 6-hrs are between 30-50% across northern MO to
central IL and southern IN, which would exceed local FFG. While the
overall system will remain fairly progressive, flow oriented
parallel to the trailing front/outflow boundary could prompt
thunderstorm redevelopment late this afternoon and evening
extending from central MO to southern IN and northern KY. This
potential for repeating storms allowed for the MDT to shift a bit
south with this update and adds additional potential for locally
severe flash flooding.

...Southeast Kansas to Southwest Missouri...
The southwestern flank of the ongoing MCS this morning is expected
to extend from south-central KS to southwest MO as 850 mb flow is
expected to become quite convergent. This may also become a focus
for reforming activity later tonight associated with additional
shortwave activity moving eastward across the Plains. However,
there is some uncertainty surrounding if this boundary can sink
further south during the day and keep storms somewhat progressive
or situated over OK and AR instead. Regardless, this all combines
for guidance to currently depict current QPF amounts of 3-4" and an
average localized max of 6". Parts of southwest MO have saturated
antecedent ground conditions due to a recent wet weather pattern,
with NASA SPoRT-LIS depicting pockets above the 80th percentile in
the 0-40cm soil moisture layer. Lastly, 00Z REFS and HREF
probabilities are agreeable with 20-60% values for exceeding 3" per
6-hrs between the two potential rounds, though may be underdone
across south-central and southeast KS for this morning's activity
based on radar and HRRR/RRFS trends.

...Upper/Middle Texas Gulf Coast to Southwest Louisiana...
A very moist atmosphere remains in place along with an upper low
over South Texas to help foster additional heavy rainfall chances,
primarily this morning, across the middle TX coast to southwest
LA. A remnant outflow boundary located in the northwest Gulf this
morning is expected to lift northward as return flow increases and
spark convection early this morning. PWs over 2.4" will allow for
any thunderstorms to contain 2-3"/hr rates and may linger in a
localized manner over similar locations and cause isolated to
scattered flash flooding. This area remains overly saturated from
prior torrential rains the last few days, which increases the
concern somewhat for additional flash flooding impacts today and
thus the addition of a SLGT risk in the excessive rainfall outlook.

...South Dakota...
Previously outlooked SLGT risk was removed with this update as the
slow-moving upper low produces scattered meandering thunderstorms,
but coverage is not expected to be enough for more than isolated
flash flooding in an area with fairly dry antecedent ground
conditions. Still, isolated flash flooding is possible and supports
the MRGL risk designation.

...Southern Mississippi, Alabama, and the Florida Panhandle...
Additional scattered thunderstorms are likely for the central Gulf
Coast states and Florida Panhandle, an area that has experienced
rounds of extreme rainfall over the last several days. A MRGL risk
remains in effect today, which highlights the potential for
isolated flash flooding. Thunderstorms are expected to remain
widely scattered as a front lifts well north towards the southern
Appalachians today. Thus, limited focus for storms to remain over
one area for enough duration to produce more than 3-4" of rain and
expectation that a MRGL will suffice even though FFG remains
drastically lower than normal for this part of the country. As
always, urban areas will be most susceptible to flash flooding
impacts should storms set up directly overhead and linger given the
moist southwesterly flow in place.

Snell
=20

Day 2
Valid 12Z Mon Jun 22 2026 - 12Z Tue Jun 23 2026

...THERE IS A SLIGHT RISK IN EFFECT FROM THE SOUTHERN PLAINS TO THE NORTHEAST...

20 UTC Update:

The inherited forecast and risk areas remain in good shape
following today's forecast cycle. Only minimal adjustments were
made to the Slight Risk area, with several focus areas of concern.
The first is the Mid-Atlantic to Northeast, generally along and
around the I-95 corridor. Between DC and NYC, the 12Z HREF
probabilities for at least 3" reach a peak of 50 to 70 percent,
with that coming in generally 6-hrs or less. So while storms may be
somewhat progressive, the possible repeating rounds and intense
rain rates (2-3"/hr) could lead to urban flash flood issues.

Further along the frontal boundary, pockets of locally heavy
rainfall are expected across the central Appalachians into the
Tennessee Valley and finally at the tail end of the frontal
boundary where it is expected to become more west to east oriented
across Oklahoma into Arkansas. This is where the storms are more
likely to train/repeat. The 12Z HREF continues to show moderate to
high probabilities (above 50 percent) for 24-hr totals exceeding
3", with some potential for isolated 5" totals.

A Marginal Risk was added to the northern Plains as another storm
system advances into the area. Warm moist air ahead of it
interacting with a frontal boundary in place will likely bring
scattered to numerous thunderstorms to portions of North Dakota,
with an isolated flash flood threat.

Taylor

previous discussion...

...Northeast and Mid-Atlantic...

The day 2 forecast period will feature a progressive trough axis
pushing from the Great Lakes to the Northeast with a trailing
frontal boundary reach southwest to the Southern Plains and above
average PWs along the axis to help create excessive rainfall
concerns. Areas of the Northeast and I-95 corridor as south as
Washington D.C. are subject to thunderstorm prospects with the
best chance for flash flooding likely to occur in the urban
footprint from D.C. to NYC with an expansion inland to central PA.
Current probs off the latest ensembles and National Blend indicate
a large zone of 30-50% probs for >2" across the aforementioned
area above with deterministic outputs closer to 2-3.5" into parts
of Southern New England. The 00z HREF (only covers through 00Z
6/23) and 00Z REFS indicate 30-60% neighborhood probabilities for
at least 2" per 6-hrs from D.C. to NYC and would be enough for
some urban flash flooding concerns. There has been additional
uncertainty farther north and east with how far to extend the SLGT
risk, but given typical mesoscale uncertainties and limited
instability, in coordination with local forecast offices the SLGT
risk was confined a bit. Look for additional refinements once the
full suite of CAMs is available, especially with increasing PWs
near the 90th climatological percentile and a nearby warm front in
the area for potential focused axis for thunderstorms.

...Southern Plains to Central Appalachians...

Across the Southern U.S., heavy precipitation will preclude
another round of convection forming along a quasi-stationary front
draped from the Southern High Plains to the Southeastern CONUS.
Probs for >1" are highest in-of the areas of Eastern OK into the
Lower Mississippi and southwestern Tennessee Valleys. Elevated
theta_E's and PWAT anomalies +2 dev. or greater indicate a
formidable environment capable of continued heavy rain potential
that will likely produce rainfall of 2-4", at least in some of the
thunderstorm activity that develops. The focal point along the
front will likely be where the heaviest rain will occur, or at
least be a low-level convergence mechanism that can enhance
regional convection. There's high enough confidence in the location
of convection for the D2 period to overlap with areas that will
have seen several inches the periods prior which led to a level 2/4
SLGT risk positioned over portions of the Southern Plains through
parts of the Southern Plains, Lower Mississippi Valley and
neighboring Tennessee Valley. The risk extends through the Smokey
Mountains up into parts of the Central Appalachians in eastern KY
up into WV as the convergence regime follows the frontal
positioning over these areas. Greatest chances for multiple rounds
of slow-moving thunderstorms capable of 2"+ hourly rainfall rates
currently appears to be over southeast OK into central AR and will
be monitored closely once CAMs are within range of the forecast
time period. Latest "longer range" REFS and HREF probabilities for
at least 3" are scattered throughout the region.

Snell
=20

Day 2
Valid 12Z Mon Jun 22 2026 - 12Z Tue Jun 23 2026

...THERE IS A SLIGHT RISK IN EFFECT FROM THE SOUTHERN PLAINS TO THE NORTHEAST...

20 UTC Update:

The inherited forecast and risk areas remain in good shape
following today's forecast cycle. Only minimal adjustments were
made to the Slight Risk area, with several focus areas of concern.
The first is the Mid-Atlantic to Northeast, generally along and
around the I-95 corridor. Between DC and NYC, the 12Z HREF
probabilities for at least 3" reach a peak of 50 to 70 percent,
with that coming in generally 6-hrs or less. So while storms may be
somewhat progressive, the possible repeating rounds and intense
rain rates (2-3"/hr) could lead to urban flash flood issues.

Further along the frontal boundary, pockets of locally heavy
rainfall are expected across the central Appalachians into the
Tennessee Valley and finally at the tail end of the frontal
boundary where it is expected to become more west to east oriented
across Oklahoma into Arkansas. This is where the storms are more
likely to train/repeat. The 12Z HREF continues to show moderate to
high probabilities (above 50 percent) for 24-hr totals exceeding
3", with some potential for isolated 5" totals.

A Marginal Risk was added to the northern Plains as another storm
system advances into the area. Warm moist air ahead of it
interacting with a frontal boundary in place will likely bring
scattered to numerous thunderstorms to portions of North Dakota,
with an isolated flash flood threat.

Taylor

previous discussion...

...Northeast and Mid-Atlantic...

The day 2 forecast period will feature a progressive trough axis
pushing from the Great Lakes to the Northeast with a trailing
frontal boundary reach southwest to the Southern Plains and above
average PWs along the axis to help create excessive rainfall
concerns. Areas of the Northeast and I-95 corridor as south as
Washington D.C. are subject to thunderstorm prospects with the
best chance for flash flooding likely to occur in the urban
footprint from D.C. to NYC with an expansion inland to central PA.
Current probs off the latest ensembles and National Blend indicate
a large zone of 30-50% probs for >2" across the aforementioned
area above with deterministic outputs closer to 2-3.5" into parts
of Southern New England. The 00z HREF (only covers through 00Z
6/23) and 00Z REFS indicate 30-60% neighborhood probabilities for
at least 2" per 6-hrs from D.C. to NYC and would be enough for
some urban flash flooding concerns. There has been additional
uncertainty farther north and east with how far to extend the SLGT
risk, but given typical mesoscale uncertainties and limited
instability, in coordination with local forecast offices the SLGT
risk was confined a bit. Look for additional refinements once the
full suite of CAMs is available, especially with increasing PWs
near the 90th climatological percentile and a nearby warm front in
the area for potential focused axis for thunderstorms.

...Southern Plains to Central Appalachians...

Across the Southern U.S., heavy precipitation will preclude
another round of convection forming along a quasi-stationary front
draped from the Southern High Plains to the Southeastern CONUS.
Probs for >1" are highest in-of the areas of Eastern OK into the
Lower Mississippi and southwestern Tennessee Valleys. Elevated
theta_E's and PWAT anomalies +2 dev. or greater indicate a
formidable environment capable of continued heavy rain potential
that will likely produce rainfall of 2-4", at least in some of the
thunderstorm activity that develops. The focal point along the
front will likely be where the heaviest rain will occur, or at
least be a low-level convergence mechanism that can enhance
regional convection. There's high enough confidence in the location
of convection for the D2 period to overlap with areas that will
have seen several inches the periods prior which led to a level 2/4
SLGT risk positioned over portions of the Southern Plains through
parts of the Southern Plains, Lower Mississippi Valley and
neighboring Tennessee Valley. The risk extends through the Smokey
Mountains up into parts of the Central Appalachians in eastern KY
up into WV as the convergence regime follows the frontal
positioning over these areas. Greatest chances for multiple rounds
of slow-moving thunderstorms capable of 2"+ hourly rainfall rates
currently appears to be over southeast OK into central AR and will
be monitored closely once CAMs are within range of the forecast
time period. Latest "longer range" REFS and HREF probabilities for
at least 3" are scattered throughout the region.

Snell
=20

Day 4 and Day 5

Valid 12Z Wed Jun 24 2026 - 12Z Fri Jun 26 2026
...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FROM PORTIONS OF
THE CENTRAL AND SOUTHERN PLAINS, LOWER MISSISSIPPI VALLEY, AND
SOUTHEASTERN U.S ON BOTH WEDNESDAY AND THURSDAY...
2030Z Discussion...

There has been a modest up-tick in deterministic/ensemble QPF
across portions of the nationa's mid-section on Day 4 where
persistent southerly flow ahead of developing low pressure in the
southern High Plaisns. Even so...the spread in placement did
little to boost confidence enough for inclusion of a Slight Risk
area and the flow around the low pressure would have a trajectory
off the terrain rather than the Gulf. No changes needed on Day 5.

Bann

Previous Discussion...
Both the D4 and D5 time frames remain in a more typical summertime
regime for the CONUS with a longwave trough over the Northern U.S.
and a dome of mid and upper ridging orienting itself across the
southwestern CONUS. Positioning of the trough/ridge pattern will
allow for persistent northwesterly flow within the mid and upper
levels across the Central and Southern High Plains over into the
Lower Mississippi Valley as progressive shortwave pulses eject out
of the Rockies and ride the prevailing northwesterlies in place
between the ridge and trough. Global deterministic and their
ensembles continue to depict a setup conducive for scattered to
widespread convective activity with general organization likely to
occur over the course of each evening as thunderstorms grow
upstream and migrate southeast within the prevailing
northwesterlies between 700-300mb. Moisture and instability will
remain elevated across much of the aforementioned areas with the
latest NAEFS output signaling a northwest to southeast alignment of
PWAT anomalies between +1 to +2 standard deviations from the WY
Front Range down to the ArkLaTex. This is historically projecting
a case of thunderstorm maturation and upscale growth over the area
outlined within the anomaly field with a correlation of a defined
theta_E ridge focused within that same zone. This would allow for
convective initiation upstream over the Front Range with organized
convective evolutions to drawn southeastward along the theta_E
gradient and oriented with the mean flow aloft. This would likely
entail convection motioning into KS/OK and pivoting eastward
towards the ArkLaTex as progs indicate the positioning of a quasi-
stationary front situated across the Lower Mississippi Valley which
would turn to a focal point for convection. ML outputs are a bit
further south with the potential as the EC-AIFS Ensemble even
promotes the threat for heavy convection towards the Red River
Basin, so there is some opportunity for southern adjustments in the
mean QPF as we move closer, so long as that signal remains stable
in the means. Overall, there has been little variance in the
recent global ensemble suite with the deterministic output also
showing very similar outcomes, at varying magnitudes with the
synoptic evolution generally stable with run- to-run continuity.

The entire setup continues through Day 5, as well, with repetition
in the mid and upper pattern as multiple vorticity maxima slide out
of the Central Rockies and migrate east- southeast through the
mean flow between the trough and ridge setup. There is now some
indication the ridging breaks down as a the heights across the west
get squashed in favor of a much stronger upper trough migrating out
of the northeastern Pacific into the Pacific Northwest and Northern
Rockies. The signal is showing up within the 500mb Height Anomalies
on both the ECENS and GEFS, a solid consensus in the pattern
breaking down somewhat as we move into the end of the week. This
will likely signal an end to the persistent northwesterlies after
the D5 window, however strong shortwave ejections will still be
plausible, as noted via the D5 window where there's growing favor
for heavy precip to occur across much of the Central Plains during
the period Thursday and Thursday night. Greatest probabilities
within the >1" PQPF are situated over southwestern NE down through
KS into OK with a general 25-50% already showing up across the
region. For a convective pattern at 5-day leads, this is a
relatively formidable signal in the threat for heavy rainfall, so
both the D4 and D5 time frames are likely going to see some short
term forecast upgrades as we gain further consensus in the
deterministic, especially as we step into the range of the CAMs.
PQPF for >2" over 72hrs (D3-5) is between 30-60% across the
ArkLaTex into the Lower Mississippi area of southern AR. This is
the most likely location for an upgrade in the risk, especially as
the recent NBM continues to pin this area as the focal point for
overlapping convection in the D3-5 window. MRGL risks remain the
forecast for both the D4 and D5 periods for the time being.

Kleebauer
=20

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!_Skq3CGVhmflsrktE_5x1p29Ofq3X1Xmhp_18V0ri9aD= RD_9FepQZLNBwJP9n36Zbz185obUBm4QsnOkmn_2EmiQYqk$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!_Skq3CGVhmflsrktE_5x1p29Ofq3X1Xmhp_18V0ri9aD= RD_9FepQZLNBwJP9n36Zbz185obUBm4QsnOkmn_2igX6MsE$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!_Skq3CGVhmflsrktE_5x1p29Ofq3X1Xmhp_18V0ri9aD= RD_9FepQZLNBwJP9n36Zbz185obUBm4QsnOkmn_2rIyXb-4$=20



$$

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FOUS30 KWBC 211947
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
347 PM EDT Sun Jun 21 2026

Day 1
Valid 1925Z Sun Jun 21 2026 - 12Z Mon Jun 22 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL IN EFFECT FOR
PARTS OF THE CENTRAL PLAINS, MIDDLE MISSISSIPPI VALLEY, AND OHIO
VALLEY...

20 UTC Update:
Pulse convection across portions of New England will continue to
produce isolated intense rain rates over 1"/hr at times over the
next several hours. Isolated flash flooding will be possible given
the above normal PWs in place and possible repeating rounds of
short but intense rainfall. See WPC MPD 490 for more details.

Elsewhere, the organized convection across the TX Gulf Coast has
largely dissipated and the Slight Risk there has been removed.

Taylor

16 UTC Update:

Current line of storms has pushed quickly through eastern Kansas
and western Missouri with well defined MCV noted. The northern
flank of this activity is expected to continue eastward into
Illinois and eventually Indiana. With diurnal heating this
afternoon, the coverage and intensity of storms will likely uptick.
While the progressive nature of this line may limit the overall
duration of any particular thunderstorm and intense rainfall, some
repeating rounds will be possible. Additionally, the wet antecedent
conditions will allow for greater runoff. All said, rainfall
amounts of 1-3" with isolated higher amounts will be possible from
eastern MO through south-central Illinois and Indiana. The key
message is that intense rain rates (locally over 2"/hr) over very
wet antecedent conditions may result in excessive runoff and
flooding, some of which could be locally significant.

Further south, the southern flank of precipitation is advancing
into northeastern OK and northwestern AR, and this activity is
likely to dissipate over the next few hours. However, it will set
up an outflow boundary and with this evening's low level jet and
another shortwave, will be the trigger for an quasi west to east
oriented line of thunderstorms. Initially, storm motions will be
slow with possible repeating/training storms. Localized 2-4" totals
with some potential for isolated higher amounts.

The main changes to the ERO was to trim the western edges of the
risk areas as the main threat of significant heavy rainfall has
lowered. The Moderate Risks were confined to eastern MO through
Indiana with the main northern shield of heavy rain with a separate
secondary area for later activity across southeast KS, southwest
MO, northeast OK, and northwest AR.

Elsewhere, minimal changes were made with some tweaks across the
Gulf Coast with the Slight Risk along the Texas Gulf Coast.

Taylor

previous discussion...

...Northern Missouri through central Illinois and Indiana...
By the start of the day 1 forecast period a potent shortwave and
related surface low/MCV are expected to eject eastward out of the
central Plains into the Midwest, driving the flash flood threat
today from Kansas to Indiana. The regional radar representation
early this morning over the central Plains is complex, with several
clusters of thunderstorms and a trailing stationary axis of heavy
rainfall across northwest Kansas. The expectation for the start of
this day 1 outlook (12Z Sat) is for these thunderstorms to organize
into a larger MCS spanning from northern MO to south-central KS.
However, compared to normal forecasts within 12 hours, there
remains some uncertainty with respect to the location of the
heaviest rainfall. However, scattered instances of flash flooding
are still expected within the MDT risk and locally significant
flash flooding impacts cannot be ruled out.

00Z CAMs and radar were utilized to define the western edge of the
SLGT and MDT risk areas and to highlight training potential over
south- central and southeast KS at the start of the forecast
period. Another axis of heavy rainfall is possible this morning and
through the day into the Midwest near the lifting warm front and
surface low/MCV. PWs and IVT above the 90th climatological
percentile (per the 00z GEFS) overlapping with soils likely still
recovering from recent heavy rain in the Midwest will lead to a
swath of at least scattered flash flooding. Antecedent ground
conditions are likely to exacerbate flash flooding where 2"/hr
rainfall rates occur, especially across parts of central IL and
central IN, where NASA SPoRT-LIS 40 cm soil moisture is above the
80th percentile and rivers remain swollen from previous rainfall
over the last week. 00z HREF and REFS neighborhood probabilities
for at least 3" per 6-hrs are between 30-50% across northern MO to
central IL and southern IN, which would exceed local FFG. While the
overall system will remain fairly progressive, flow oriented
parallel to the trailing front/outflow boundary could prompt
thunderstorm redevelopment late this afternoon and evening
extending from central MO to southern IN and northern KY. This
potential for repeating storms allowed for the MDT to shift a bit
south with this update and adds additional potential for locally
severe flash flooding.

...Southeast Kansas to Southwest Missouri...
The southwestern flank of the ongoing MCS this morning is expected
to extend from south-central KS to southwest MO as 850 mb flow is
expected to become quite convergent. This may also become a focus
for reforming activity later tonight associated with additional
shortwave activity moving eastward across the Plains. However,
there is some uncertainty surrounding if this boundary can sink
further south during the day and keep storms somewhat progressive
or situated over OK and AR instead. Regardless, this all combines
for guidance to currently depict current QPF amounts of 3-4" and an
average localized max of 6". Parts of southwest MO have saturated
antecedent ground conditions due to a recent wet weather pattern,
with NASA SPoRT-LIS depicting pockets above the 80th percentile in
the 0-40cm soil moisture layer. Lastly, 00Z REFS and HREF
probabilities are agreeable with 20-60% values for exceeding 3" per
6-hrs between the two potential rounds, though may be underdone
across south-central and southeast KS for this morning's activity
based on radar and HRRR/RRFS trends.

...Upper/Middle Texas Gulf Coast to Southwest Louisiana...
A very moist atmosphere remains in place along with an upper low
over South Texas to help foster additional heavy rainfall chances,
primarily this morning, across the middle TX coast to southwest
LA. A remnant outflow boundary located in the northwest Gulf this
morning is expected to lift northward as return flow increases and
spark convection early this morning. PWs over 2.4" will allow for
any thunderstorms to contain 2-3"/hr rates and may linger in a
localized manner over similar locations and cause isolated to
scattered flash flooding. This area remains overly saturated from
prior torrential rains the last few days, which increases the
concern somewhat for additional flash flooding impacts today and
thus the addition of a SLGT risk in the excessive rainfall outlook.

...South Dakota...
Previously outlooked SLGT risk was removed with this update as the
slow-moving upper low produces scattered meandering thunderstorms,
but coverage is not expected to be enough for more than isolated
flash flooding in an area with fairly dry antecedent ground
conditions. Still, isolated flash flooding is possible and supports
the MRGL risk designation.

...Southern Mississippi, Alabama, and the Florida Panhandle...
Additional scattered thunderstorms are likely for the central Gulf
Coast states and Florida Panhandle, an area that has experienced
rounds of extreme rainfall over the last several days. A MRGL risk
remains in effect today, which highlights the potential for
isolated flash flooding. Thunderstorms are expected to remain
widely scattered as a front lifts well north towards the southern
Appalachians today. Thus, limited focus for storms to remain over
one area for enough duration to produce more than 3-4" of rain and
expectation that a MRGL will suffice even though FFG remains
drastically lower than normal for this part of the country. As
always, urban areas will be most susceptible to flash flooding
impacts should storms set up directly overhead and linger given the
moist southwesterly flow in place.

Snell
=20

Day 2
Valid 12Z Mon Jun 22 2026 - 12Z Tue Jun 23 2026

...THERE IS A SLIGHT RISK IN EFFECT FROM THE SOUTHERN PLAINS TO THE NORTHEAST...

20 UTC Update:

The inherited forecast and risk areas remain in good shape
following today's forecast cycle. Only minimal adjustments were
made to the Slight Risk area, with several focus areas of concern.
The first is the Mid-Atlantic to Northeast, generally along and
around the I-95 corridor. Between DC and NYC, the 12Z HREF
probabilities for at least 3" reach a peak of 50 to 70 percent,
with that coming in generally 6-hrs or less. So while storms may be
somewhat progressive, the possible repeating rounds and intense
rain rates (2-3"/hr) could lead to urban flash flood issues.

Further along the frontal boundary, pockets of locally heavy
rainfall are expected across the central Appalachians into the
Tennessee Valley and finally at the tail end of the frontal
boundary where it is expected to become more west to east oriented
across Oklahoma into Arkansas. This is where the storms are more
likely to train/repeat. The 12Z HREF continues to show moderate to
high probabilities (above 50 percent) for 24-hr totals exceeding
3", with some potential for isolated 5" totals.

A Marginal Risk was added to the northern Plains as another storm
system advances into the area. Warm moist air ahead of it
interacting with a frontal boundary in place will likely bring
scattered to numerous thunderstorms to portions of North Dakota,
with an isolated flash flood threat.

Taylor

previous discussion...

...Northeast and Mid-Atlantic...

The day 2 forecast period will feature a progressive trough axis
pushing from the Great Lakes to the Northeast with a trailing
frontal boundary reach southwest to the Southern Plains and above
average PWs along the axis to help create excessive rainfall
concerns. Areas of the Northeast and I-95 corridor as south as
Washington D.C. are subject to thunderstorm prospects with the
best chance for flash flooding likely to occur in the urban
footprint from D.C. to NYC with an expansion inland to central PA.
Current probs off the latest ensembles and National Blend indicate
a large zone of 30-50% probs for >2" across the aforementioned
area above with deterministic outputs closer to 2-3.5" into parts
of Southern New England. The 00z HREF (only covers through 00Z
6/23) and 00Z REFS indicate 30-60% neighborhood probabilities for
at least 2" per 6-hrs from D.C. to NYC and would be enough for
some urban flash flooding concerns. There has been additional
uncertainty farther north and east with how far to extend the SLGT
risk, but given typical mesoscale uncertainties and limited
instability, in coordination with local forecast offices the SLGT
risk was confined a bit. Look for additional refinements once the
full suite of CAMs is available, especially with increasing PWs
near the 90th climatological percentile and a nearby warm front in
the area for potential focused axis for thunderstorms.

...Southern Plains to Central Appalachians...

Across the Southern U.S., heavy precipitation will preclude
another round of convection forming along a quasi-stationary front
draped from the Southern High Plains to the Southeastern CONUS.
Probs for >1" are highest in-of the areas of Eastern OK into the
Lower Mississippi and southwestern Tennessee Valleys. Elevated
theta_E's and PWAT anomalies +2 dev. or greater indicate a
formidable environment capable of continued heavy rain potential
that will likely produce rainfall of 2-4", at least in some of the
thunderstorm activity that develops. The focal point along the
front will likely be where the heaviest rain will occur, or at
least be a low-level convergence mechanism that can enhance
regional convection. There's high enough confidence in the location
of convection for the D2 period to overlap with areas that will
have seen several inches the periods prior which led to a level 2/4
SLGT risk positioned over portions of the Southern Plains through
parts of the Southern Plains, Lower Mississippi Valley and
neighboring Tennessee Valley. The risk extends through the Smokey
Mountains up into parts of the Central Appalachians in eastern KY
up into WV as the convergence regime follows the frontal
positioning over these areas. Greatest chances for multiple rounds
of slow-moving thunderstorms capable of 2"+ hourly rainfall rates
currently appears to be over southeast OK into central AR and will
be monitored closely once CAMs are within range of the forecast
time period. Latest "longer range" REFS and HREF probabilities for
at least 3" are scattered throughout the region.

Snell
=20

Day 3
Valid 12Z Tue Jun 23 2026 - 12Z Wed Jun 24 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL IN EFFECT FROM
PARTS OF THE CENTRAL PLAINS TO THE SOUTHEAST...

20 UTC Update:

No significant changes were made to the inherited risk areas with
today's forecast cycle. A frontal boundary draped across portions
of the Plains into the Southeast will be the main focus for
convection that could produce locally heavy rainfall. A secondary
area of concern would be the CO Front Range as another frontal
boundary drops southward.

Taylor

---previous discussion---

...Central Plains to Southeast...

Day 3 is a transition period into a more typical summertime regime
for the CONUS with a longwave trough over the Northern U.S. and a
dome of mid and upper ridging orienting itself across the
southwestern CONUS. Positioning of the trough/ridge pattern will
cause a persistent northwesterly flow within the mid and upper
levels across the Central and Southern High Plains over into the
Lower Mississippi Valley as progressive shortwave pulses eject out
of the Rockies and ride the prevailing northwesterlies in place
between the ridge and trough. This highlights potential for MCS
development and flash flooding scenarios from the Front Range and
points southeast as the steering flow orients between the base of
the trough and the northeastern flank of the ridge. This is
historically projecting a case of thunderstorm maturation and
upscale growth over the area between CO/KS down through OK/TX with
potentially the Red River Basin as a focus for thunderstorm
activity. Eventually, this ends up migrating into the ArkLaTex
and/or Lower Mississippi area which is showing up in the QPF
footprint on ensembles. There has been little variance in the
recent global ensemble suite with the deterministic output also
showing very similar outcomes, at varying magnitudes with the
synoptic evolution generally stable with run-to-run continuity.
Should CAMs come into better focus for aforementioned MCS activity
over the region, a SLGT risk could be introduced in future updates.

Snell
=20

Day 4 and Day 5

Valid 12Z Wed Jun 24 2026 - 12Z Fri Jun 26 2026
...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FROM PORTIONS OF
THE CENTRAL AND SOUTHERN PLAINS, LOWER MISSISSIPPI VALLEY, AND
SOUTHEASTERN U.S ON BOTH WEDNESDAY AND THURSDAY...

2030Z Discussion...
There has been a modest up-tick in deterministic/ensemble QPF
across portions of the nationa's mid-section on Day 4 where
persistent southerly flow ahead of developing low pressure in the
southern High Plaisns. Even so...the spread in placement did
little to boost confidence enough for inclusion of a Slight Risk
area and the flow around the low pressure would have a trajectory
off the terrain rather than the Gulf. No changes needed on Day 5.

Bann

Previous Discussion...
Both the D4 and D5 time frames remain in a more typical summertime
regime for the CONUS with a longwave trough over the Northern U.S.
and a dome of mid and upper ridging orienting itself across the
southwestern CONUS. Positioning of the trough/ridge pattern will
allow for persistent northwesterly flow within the mid and upper
levels across the Central and Southern High Plains over into the
Lower Mississippi Valley as progressive shortwave pulses eject out
of the Rockies and ride the prevailing northwesterlies in place
between the ridge and trough. Global deterministic and their
ensembles continue to depict a setup conducive for scattered to
widespread convective activity with general organization likely to
occur over the course of each evening as thunderstorms grow
upstream and migrate southeast within the prevailing
northwesterlies between 700-300mb. Moisture and instability will
remain elevated across much of the aforementioned areas with the
latest NAEFS output signaling a northwest to southeast alignment of
PWAT anomalies between +1 to +2 standard deviations from the WY
Front Range down to the ArkLaTex. This is historically projecting
a case of thunderstorm maturation and upscale growth over the area
outlined within the anomaly field with a correlation of a defined
theta_E ridge focused within that same zone. This would allow for
convective initiation upstream over the Front Range with organized
convective evolutions to drawn southeastward along the theta_E
gradient and oriented with the mean flow aloft. This would likely
entail convection motioning into KS/OK and pivoting eastward
towards the ArkLaTex as progs indicate the positioning of a quasi-
stationary front situated across the Lower Mississippi Valley which
would turn to a focal point for convection. ML outputs are a bit
further south with the potential as the EC-AIFS Ensemble even
promotes the threat for heavy convection towards the Red River
Basin, so there is some opportunity for southern adjustments in the
mean QPF as we move closer, so long as that signal remains stable
in the means. Overall, there has been little variance in the
recent global ensemble suite with the deterministic output also
showing very similar outcomes, at varying magnitudes with the
synoptic evolution generally stable with run- to-run continuity.

The entire setup continues through Day 5, as well, with repetition
in the mid and upper pattern as multiple vorticity maxima slide out
of the Central Rockies and migrate east- southeast through the
mean flow between the trough and ridge setup. There is now some
indication the ridging breaks down as a the heights across the west
get squashed in favor of a much stronger upper trough migrating out
of the northeastern Pacific into the Pacific Northwest and Northern
Rockies. The signal is showing up within the 500mb Height Anomalies
on both the ECENS and GEFS, a solid consensus in the pattern
breaking down somewhat as we move into the end of the week. This
will likely signal an end to the persistent northwesterlies after
the D5 window, however strong shortwave ejections will still be
plausible, as noted via the D5 window where there's growing favor
for heavy precip to occur across much of the Central Plains during
the period Thursday and Thursday night. Greatest probabilities
within the >1" PQPF are situated over southwestern NE down through
KS into OK with a general 25-50% already showing up across the
region. For a convective pattern at 5-day leads, this is a
relatively formidable signal in the threat for heavy rainfall, so
both the D4 and D5 time frames are likely going to see some short
term forecast upgrades as we gain further consensus in the
deterministic, especially as we step into the range of the CAMs.
PQPF for >2" over 72hrs (D3-5) is between 30-60% across the
ArkLaTex into the Lower Mississippi area of southern AR. This is
the most likely location for an upgrade in the risk, especially as
the recent NBM continues to pin this area as the focal point for
overlapping convection in the D3-5 window. MRGL risks remain the
forecast for both the D4 and D5 periods for the time being.

Kleebauer
=20

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!6-CJ5AG7j5j71ORSdMEU7UG5apa8CxjfReuBC4Kjwgfp= 1hJFPyHh_LQU4igYO1K5jsHegwUEUeDQT71CRoVN187RB2U$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!6-CJ5AG7j5j71ORSdMEU7UG5apa8CxjfReuBC4Kjwgfp= 1hJFPyHh_LQU4igYO1K5jsHegwUEUeDQT71CRoVNr690YwU$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!6-CJ5AG7j5j71ORSdMEU7UG5apa8CxjfReuBC4Kjwgfp= 1hJFPyHh_LQU4igYO1K5jsHegwUEUeDQT71CRoVNtsy_LQM$=20



$$

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FOUS30 KWBC 220052
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
852 PM EDT Sun Jun 21 2026

Day 1
Valid 01Z Mon Jun 22 2026 - 12Z Mon Jun 22 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL IN EFFECT FOR
PARTS OF THE CENTRAL PLAINS, MIDDLE MISSISSIPPI VALLEY, AND OHIO
VALLEY...

01Z Update:
Changes made to the on-going outlook were largely done to remove
territories where the front has already moved through. Guidance
from the day-shift continued to support the Moderate risk areas
from southern Indiana southwestward into the Central/Southern
Plains overnight...so no changes there or to the Marginal Risk area
in parts of Florida/Alabama/Georgia. Convection had weakened
quickly in Maine and the Marginal was removed.

Bann

16 UTC Update:
Current line of storms has pushed quickly through eastern Kansas
and western Missouri with well defined MCV noted. The northern
flank of this activity is expected to continue eastward into
Illinois and eventually Indiana. With diurnal heating this
afternoon, the coverage and intensity of storms will likely uptick.
While the progressive nature of this line may limit the overall
duration of any particular thunderstorm and intense rainfall, some
repeating rounds will be possible. Additionally, the wet antecedent
conditions will allow for greater runoff. All said, rainfall
amounts of 1-3" with isolated higher amounts will be possible from
eastern MO through south-central Illinois and Indiana. The key
message is that intense rain rates (locally over 2"/hr) over very
wet antecedent conditions may result in excessive runoff and
flooding, some of which could be locally significant.
Further south, the southern flank of precipitation is advancing
into northeastern OK and northwestern AR, and this activity is
likely to dissipate over the next few hours. However, it will set
up an outflow boundary and with this evening's low level jet and
another shortwave, will be the trigger for an quasi west to east
oriented line of thunderstorms. Initially, storm motions will be
slow with possible repeating/training storms. Localized 2-4" totals
with some potential for isolated higher amounts.
The main changes to the ERO was to trim the western edges of the
risk areas as the main threat of significant heavy rainfall has
lowered. The Moderate Risks were confined to eastern MO through
Indiana with the main northern shield of heavy rain with a separate
secondary area for later activity across southeast KS, southwest
MO, northeast OK, and northwest AR.

Elsewhere, minimal changes were made with some tweaks across the
Gulf Coast with the Slight Risk along the Texas Gulf Coast.

Taylor

previous discussion...
...Northern Missouri through central Illinois and Indiana...
By the start of the day 1 forecast period a potent shortwave and
related surface low/MCV are expected to eject eastward out of the
central Plains into the Midwest, driving the flash flood threat
today from Kansas to Indiana. The regional radar representation
early this morning over the central Plains is complex, with several
clusters of thunderstorms and a trailing stationary axis of heavy
rainfall across northwest Kansas. The expectation for the start of
this day 1 outlook (12Z Sat) is for these thunderstorms to organize
into a larger MCS spanning from northern MO to south-central KS.
However, compared to normal forecasts within 12 hours, there
remains some uncertainty with respect to the location of the
heaviest rainfall. However, scattered instances of flash flooding
are still expected within the MDT risk and locally significant
flash flooding impacts cannot be ruled out.

00Z CAMs and radar were utilized to define the western edge of the
SLGT and MDT risk areas and to highlight training potential over
south- central and southeast KS at the start of the forecast
period. Another axis of heavy rainfall is possible this morning and
through the day into the Midwest near the lifting warm front and
surface low/MCV. PWs and IVT above the 90th climatological
percentile (per the 00z GEFS) overlapping with soils likely still
recovering from recent heavy rain in the Midwest will lead to a
swath of at least scattered flash flooding. Antecedent ground
conditions are likely to exacerbate flash flooding where 2"/hr
rainfall rates occur, especially across parts of central IL and
central IN, where NASA SPoRT-LIS 40 cm soil moisture is above the
80th percentile and rivers remain swollen from previous rainfall
over the last week. 00z HREF and REFS neighborhood probabilities
for at least 3" per 6-hrs are between 30-50% across northern MO to
central IL and southern IN, which would exceed local FFG. While the
overall system will remain fairly progressive, flow oriented
parallel to the trailing front/outflow boundary could prompt
thunderstorm redevelopment late this afternoon and evening
extending from central MO to southern IN and northern KY. This
potential for repeating storms allowed for the MDT to shift a bit
south with this update and adds additional potential for locally
severe flash flooding.

...Southeast Kansas to Southwest Missouri...
The southwestern flank of the ongoing MCS this morning is expected
to extend from south-central KS to southwest MO as 850 mb flow is
expected to become quite convergent. This may also become a focus
for reforming activity later tonight associated with additional
shortwave activity moving eastward across the Plains. However,
there is some uncertainty surrounding if this boundary can sink
further south during the day and keep storms somewhat progressive
or situated over OK and AR instead. Regardless, this all combines
for guidance to currently depict current QPF amounts of 3-4" and an
average localized max of 6". Parts of southwest MO have saturated
antecedent ground conditions due to a recent wet weather pattern,
with NASA SPoRT-LIS depicting pockets above the 80th percentile in
the 0-40cm soil moisture layer. Lastly, 00Z REFS and HREF
probabilities are agreeable with 20-60% values for exceeding 3" per
6-hrs between the two potential rounds, though may be underdone
across south-central and southeast KS for this morning's activity
based on radar and HRRR/RRFS trends.

...Upper/Middle Texas Gulf Coast to Southwest Louisiana...
A very moist atmosphere remains in place along with an upper low
over South Texas to help foster additional heavy rainfall chances,
primarily this morning, across the middle TX coast to southwest
LA. A remnant outflow boundary located in the northwest Gulf this
morning is expected to lift northward as return flow increases and
spark convection early this morning. PWs over 2.4" will allow for
any thunderstorms to contain 2-3"/hr rates and may linger in a
localized manner over similar locations and cause isolated to
scattered flash flooding. This area remains overly saturated from
prior torrential rains the last few days, which increases the
concern somewhat for additional flash flooding impacts today and
thus the addition of a SLGT risk in the excessive rainfall outlook.

...South Dakota...
Previously outlooked SLGT risk was removed with this update as the
slow-moving upper low produces scattered meandering thunderstorms,
but coverage is not expected to be enough for more than isolated
flash flooding in an area with fairly dry antecedent ground
conditions. Still, isolated flash flooding is possible and supports
the MRGL risk designation.

...Southern Mississippi, Alabama, and the Florida Panhandle...
Additional scattered thunderstorms are likely for the central Gulf
Coast states and Florida Panhandle, an area that has experienced
rounds of extreme rainfall over the last several days. A MRGL risk
remains in effect today, which highlights the potential for
isolated flash flooding. Thunderstorms are expected to remain
widely scattered as a front lifts well north towards the southern
Appalachians today. Thus, limited focus for storms to remain over
one area for enough duration to produce more than 3-4" of rain and
expectation that a MRGL will suffice even though FFG remains
drastically lower than normal for this part of the country. As
always, urban areas will be most susceptible to flash flooding
impacts should storms set up directly overhead and linger given the
moist southwesterly flow in place.
Snell
=20

Day 2
Valid 12Z Mon Jun 22 2026 - 12Z Tue Jun 23 2026

...THERE IS A SLIGHT RISK IN EFFECT FROM THE SOUTHERN PLAINS TO THE NORTHEAST...

20 UTC Update:

The inherited forecast and risk areas remain in good shape
following today's forecast cycle. Only minimal adjustments were
made to the Slight Risk area, with several focus areas of concern.
The first is the Mid-Atlantic to Northeast, generally along and
around the I-95 corridor. Between DC and NYC, the 12Z HREF
probabilities for at least 3" reach a peak of 50 to 70 percent,
with that coming in generally 6-hrs or less. So while storms may be
somewhat progressive, the possible repeating rounds and intense
rain rates (2-3"/hr) could lead to urban flash flood issues.

Further along the frontal boundary, pockets of locally heavy
rainfall are expected across the central Appalachians into the
Tennessee Valley and finally at the tail end of the frontal
boundary where it is expected to become more west to east oriented
across Oklahoma into Arkansas. This is where the storms are more
likely to train/repeat. The 12Z HREF continues to show moderate to
high probabilities (above 50 percent) for 24-hr totals exceeding
3", with some potential for isolated 5" totals.

A Marginal Risk was added to the northern Plains as another storm
system advances into the area. Warm moist air ahead of it
interacting with a frontal boundary in place will likely bring
scattered to numerous thunderstorms to portions of North Dakota,
with an isolated flash flood threat.

Taylor

previous discussion...

...Northeast and Mid-Atlantic...

The day 2 forecast period will feature a progressive trough axis
pushing from the Great Lakes to the Northeast with a trailing
frontal boundary reach southwest to the Southern Plains and above
average PWs along the axis to help create excessive rainfall
concerns. Areas of the Northeast and I-95 corridor as south as
Washington D.C. are subject to thunderstorm prospects with the
best chance for flash flooding likely to occur in the urban
footprint from D.C. to NYC with an expansion inland to central PA.
Current probs off the latest ensembles and National Blend indicate
a large zone of 30-50% probs for >2" across the aforementioned
area above with deterministic outputs closer to 2-3.5" into parts
of Southern New England. The 00z HREF (only covers through 00Z
6/23) and 00Z REFS indicate 30-60% neighborhood probabilities for
at least 2" per 6-hrs from D.C. to NYC and would be enough for
some urban flash flooding concerns. There has been additional
uncertainty farther north and east with how far to extend the SLGT
risk, but given typical mesoscale uncertainties and limited
instability, in coordination with local forecast offices the SLGT
risk was confined a bit. Look for additional refinements once the
full suite of CAMs is available, especially with increasing PWs
near the 90th climatological percentile and a nearby warm front in
the area for potential focused axis for thunderstorms.

...Southern Plains to Central Appalachians...

Across the Southern U.S., heavy precipitation will preclude
another round of convection forming along a quasi-stationary front
draped from the Southern High Plains to the Southeastern CONUS.
Probs for >1" are highest in-of the areas of Eastern OK into the
Lower Mississippi and southwestern Tennessee Valleys. Elevated
theta_E's and PWAT anomalies +2 dev. or greater indicate a
formidable environment capable of continued heavy rain potential
that will likely produce rainfall of 2-4", at least in some of the
thunderstorm activity that develops. The focal point along the
front will likely be where the heaviest rain will occur, or at
least be a low-level convergence mechanism that can enhance
regional convection. There's high enough confidence in the location
of convection for the D2 period to overlap with areas that will
have seen several inches the periods prior which led to a level 2/4
SLGT risk positioned over portions of the Southern Plains through
parts of the Southern Plains, Lower Mississippi Valley and
neighboring Tennessee Valley. The risk extends through the Smokey
Mountains up into parts of the Central Appalachians in eastern KY
up into WV as the convergence regime follows the frontal
positioning over these areas. Greatest chances for multiple rounds
of slow-moving thunderstorms capable of 2"+ hourly rainfall rates
currently appears to be over southeast OK into central AR and will
be monitored closely once CAMs are within range of the forecast
time period. Latest "longer range" REFS and HREF probabilities for
at least 3" are scattered throughout the region.

Snell
=20

Day 3
Valid 12Z Tue Jun 23 2026 - 12Z Wed Jun 24 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL IN EFFECT FROM
PARTS OF THE CENTRAL PLAINS TO THE SOUTHEAST...

20 UTC Update:

No significant changes were made to the inherited risk areas with
today's forecast cycle. A frontal boundary draped across portions
of the Plains into the Southeast will be the main focus for
convection that could produce locally heavy rainfall. A secondary
area of concern would be the CO Front Range as another frontal
boundary drops southward.

Taylor

---previous discussion---

...Central Plains to Southeast...

Day 3 is a transition period into a more typical summertime regime
for the CONUS with a longwave trough over the Northern U.S. and a
dome of mid and upper ridging orienting itself across the
southwestern CONUS. Positioning of the trough/ridge pattern will
cause a persistent northwesterly flow within the mid and upper
levels across the Central and Southern High Plains over into the
Lower Mississippi Valley as progressive shortwave pulses eject out
of the Rockies and ride the prevailing northwesterlies in place
between the ridge and trough. This highlights potential for MCS
development and flash flooding scenarios from the Front Range and
points southeast as the steering flow orients between the base of
the trough and the northeastern flank of the ridge. This is
historically projecting a case of thunderstorm maturation and
upscale growth over the area between CO/KS down through OK/TX with
potentially the Red River Basin as a focus for thunderstorm
activity. Eventually, this ends up migrating into the ArkLaTex
and/or Lower Mississippi area which is showing up in the QPF
footprint on ensembles. There has been little variance in the
recent global ensemble suite with the deterministic output also
showing very similar outcomes, at varying magnitudes with the
synoptic evolution generally stable with run-to-run continuity.
Should CAMs come into better focus for aforementioned MCS activity
over the region, a SLGT risk could be introduced in future updates.

Snell
=20

Day 4 and Day 5

Valid 12Z Wed Jun 24 2026 - 12Z Fri Jun 26 2026
...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FROM PORTIONS OF
THE CENTRAL AND SOUTHERN PLAINS, LOWER MISSISSIPPI VALLEY, AND
SOUTHEASTERN U.S ON BOTH WEDNESDAY AND THURSDAY...

2030Z Discussion...
There has been a modest up-tick in deterministic/ensemble QPF
across portions of the nationa's mid-section on Day 4 where
persistent southerly flow ahead of developing low pressure in the
southern High Plaisns. Even so...the spread in placement did
little to boost confidence enough for inclusion of a Slight Risk
area and the flow around the low pressure would have a trajectory
off the terrain rather than the Gulf. No changes needed on Day 5.
Bann

Previous Discussion...
Both the D4 and D5 time frames remain in a more typical summertime
regime for the CONUS with a longwave trough over the Northern U.S.
and a dome of mid and upper ridging orienting itself across the
southwestern CONUS. Positioning of the trough/ridge pattern will
allow for persistent northwesterly flow within the mid and upper
levels across the Central and Southern High Plains over into the
Lower Mississippi Valley as progressive shortwave pulses eject out
of the Rockies and ride the prevailing northwesterlies in place
between the ridge and trough. Global deterministic and their
ensembles continue to depict a setup conducive for scattered to
widespread convective activity with general organization likely to
occur over the course of each evening as thunderstorms grow
upstream and migrate southeast within the prevailing
northwesterlies between 700-300mb. Moisture and instability will
remain elevated across much of the aforementioned areas with the
latest NAEFS output signaling a northwest to southeast alignment of
PWAT anomalies between +1 to +2 standard deviations from the WY
Front Range down to the ArkLaTex. This is historically projecting
a case of thunderstorm maturation and upscale growth over the area
outlined within the anomaly field with a correlation of a defined
theta_E ridge focused within that same zone. This would allow for
convective initiation upstream over the Front Range with organized
convective evolutions to drawn southeastward along the theta_E
gradient and oriented with the mean flow aloft. This would likely
entail convection motioning into KS/OK and pivoting eastward
towards the ArkLaTex as progs indicate the positioning of a quasi-
stationary front situated across the Lower Mississippi Valley which
would turn to a focal point for convection. ML outputs are a bit
further south with the potential as the EC-AIFS Ensemble even
promotes the threat for heavy convection towards the Red River
Basin, so there is some opportunity for southern adjustments in the
mean QPF as we move closer, so long as that signal remains stable
in the means. Overall, there has been little variance in the
recent global ensemble suite with the deterministic output also
showing very similar outcomes, at varying magnitudes with the
synoptic evolution generally stable with run- to-run continuity.

The entire setup continues through Day 5, as well, with repetition
in the mid and upper pattern as multiple vorticity maxima slide out
of the Central Rockies and migrate east- southeast through the
mean flow between the trough and ridge setup. There is now some
indication the ridging breaks down as a the heights across the west
get squashed in favor of a much stronger upper trough migrating out
of the northeastern Pacific into the Pacific Northwest and Northern
Rockies. The signal is showing up within the 500mb Height Anomalies
on both the ECENS and GEFS, a solid consensus in the pattern
breaking down somewhat as we move into the end of the week. This
will likely signal an end to the persistent northwesterlies after
the D5 window, however strong shortwave ejections will still be
plausible, as noted via the D5 window where there's growing favor
for heavy precip to occur across much of the Central Plains during
the period Thursday and Thursday night. Greatest probabilities
within the >1" PQPF are situated over southwestern NE down through
KS into OK with a general 25-50% already showing up across the
region. For a convective pattern at 5-day leads, this is a
relatively formidable signal in the threat for heavy rainfall, so
both the D4 and D5 time frames are likely going to see some short
term forecast upgrades as we gain further consensus in the
deterministic, especially as we step into the range of the CAMs.
PQPF for >2" over 72hrs (D3-5) is between 30-60% across the
ArkLaTex into the Lower Mississippi area of southern AR. This is
the most likely location for an upgrade in the risk, especially as
the recent NBM continues to pin this area as the focal point for
overlapping convection in the D3-5 window. MRGL risks remain the
forecast for both the D4 and D5 periods for the time being.

Kleebauer
=20

Day 1 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/94epoints.txt__;!!DZ3fjg!6WavPu8KbQW4S5Z_YFi8GcBlV5nSqJuL0HfuKKnl6LZH= iRfWVt_LHAoJfQ2rvF0lMnDMtz5MaNZ01N5Wef0ugorextA$=20
Day 2 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/98epoints.txt__;!!DZ3fjg!6WavPu8KbQW4S5Z_YFi8GcBlV5nSqJuL0HfuKKnl6LZH= iRfWVt_LHAoJfQ2rvF0lMnDMtz5MaNZ01N5Wef0unuB8fHc$=20
Day 3 threat area: https://urldefense.com/v3/__https://www.wpc.ncep.noaa.go= v/qpf/99epoints.txt__;!!DZ3fjg!6WavPu8KbQW4S5Z_YFi8GcBlV5nSqJuL0HfuKKnl6LZH= iRfWVt_LHAoJfQ2rvF0lMnDMtz5MaNZ01N5Wef0u19vpjQs$=20



$$

=3D =3D =3D
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