ACUS48 KWNS 250846
SWOD48
SPC AC 250844

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0344 AM CDT Wed Mar 25 2026

Valid 281200Z - 021200Z

...DISCUSSION...
Severe thunderstorm potential remains limited for this weekend,
though a gradual increase in some severe threat is anticipated by
the middle of next week. In the wake of a cold frontal passage on
D3/Friday into D4/Saturday, surface high pressure building over the
eastern Plains and OH Valley will maintain dry and stable conditions
for most regions east of the Rockies. Concurrently, a slight
re-amplification of an upper-level ridge this weekend over the
Southwest/West Coast will maintain warm and dry conditions for the
southwestern CONUS. Long-range ensemble guidance continues to show a
reasonably consistent signal in the slow eastward migration of the
upper ridge through early next week. As this occurs, surface high
pressure will gradually shift off the East Coast and promote
moisture return into the Plains and MS Valley. Tight clustering of
GEFS members lends high confidence in the potential for a return of
slightly above seasonal moisture by the D6/Monday to D7/Tuesday time
frame. Thunderstorm chances should steadily increase through
mid-week as southwesterly flow aloft becomes increasingly
predominant and promotes ascent/lapse-rate advection over the
northwestern fringe of the returning moisture. Extended-range
guidance hints at severe thunderstorm potential through the
D6/Monday to D8/Wednesday time frame - mainly across the upper MS Valley/Midwest within the warm conveyor region of an organizing
cyclone. While confidence in the overall synoptic evolution through
next week is high, notable run-to-run variability in the convective
environment forecast beyond D6 suggests predictability remains too
limited to warrant highlights at this time.

..Moore.. 03/25/2026

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ACUS48 KWNS 260850
SWOD48
SPC AC 260848

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0348 AM CDT Thu Mar 26 2026

Valid 291200Z - 031200Z

...DISCUSSION...
Severe weather potential will remain low through the end of the
upcoming weekend, and while a gradual increase in severe weather
potential is anticipated through next week, predictability remains
limited. Extended-range deterministic and ensemble solutions
continue to generally show good agreement in the eastward
translation of the upper ridge currently over the Southwest towards
the East Coast through the middle of next week. This will not only
result in increasing southwesterly flow over the central CONUS, but
will also promote lee troughing/cyclogenesis with an attendant
uptick in moisture return into the Plains/MS Valley.

Recent GEFS forecasts show high confidence in a return of slightly
above seasonal moisture into the eastern Plains and Midwest by the
D5/Monday to D6/Tuesday time frame. Severe thunderstorm potential is
expected to generally increase during this period as weak impulses
embedded within the broader southwest flow regime overspread the
returning moisture. Based on more bullish deterministic solutions,
some severe risk may materialize across the Midwest late D5/Monday
into D6/Tuesday within a warm frontal zone, and potentially across
the central Plains on D7/Wednesday or D8/Thursday as a cold front
pushes southeast in tandem with the intensification of a surface
low.

While these signals are noted, run-to-run variability among
deterministic guidance remains fairly high regarding the
evolution/placement of surface features and convective environments
beyond D6/Tuesday. Latest GEFS and ECENS guidance, as well as
long-range ensemble clustering and extended calibrated guidance,
show a substantial increase in variance by mid-week, which implies
limited confidence in any particular solution. While not surprising
at this range and with an upper-level regime shift yet to occur, it
remains unclear when predictability of any mid-week severe threat
will substantially improve.

..Moore.. 03/26/2026

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ACUS48 KWNS 270855
SWOD48
SPC AC 270853

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0353 AM CDT Fri Mar 27 2026

Valid 301200Z - 041200Z

...DISCUSSION...
An uptick in severe thunderstorm potential is expected through the
upcoming work week and heading into next weekend. Long-range
ensemble guidance continues to show a strong signal for a return to
mean troughing across the western to central CONUS as a long-wave
ridge gradually de-amplifies and shifts east. This upper-level flow
regime will promote steady lee troughing/cyclogenesis along the High
Plains, which in conjunction with the placement of a surface high
off the East Coast, will promote moisture return northward into the
Plains and MS Valley. Strong to severe thunderstorms appear possible
multiple days next week as ascent associated with upper disturbances
embedded within the mean flow regime overspread the moisture plume.

...D4/Monday - Upper Mississippi Valley...
A low-amplitude upper wave is forecast to traverse the U.S./Canadian
border during the D4/Monday to D5/Tuesday time frame. As this
occurs, surface cyclogenesis is expected across the northern Plains.
A broad swath of isentropic ascent with in the warm conveyor of the
developing cyclone will likely support showers and isolated to
scattered thunderstorms across portions of the upper MS Valley late
Monday. A few deterministic solutions, notably the recent 00z ECMWF,
hint that the convective environment will be conducive for organized convection, including the potential for elevated supercells.
However, ensemble agreement regarding this potential is limited.

...D5/Tuesday - Lake Michigan Vicinity...
Confidence is gradually increasing in a regional severe weather
threat across parts of the upper Great Lakes for D5/Tuesday. Over
the past 24 hours, model guidance has come into somewhat better
agreement regarding the timing and evolution of the northern Plains
surface low through as it translates east and intensifies across the
Great Lakes region Tuesday into early Wednesday. Above-seasonal
moisture return northward into the Great Lakes region is anticipated
by late Tuesday, which should support adequate buoyancy for deep
convection. Thunderstorm development appears likely along a trailing
cold front as it pushes southeast into the Midwest and MS Valley.
Based on ensemble guidance, the best convective environment may
reside across the Lake Michigan vicinity where mid/upper-level flow
should be stronger in vicinity to the upper jet and may be more
orthogonal to the front and supportive of more robust convection
compared to locations further south.

Despite the trend towards a more consolidated solution, notable
discrepancies remain pertaining to the propagation speed of the
upper wave and surface low, which introduces uncertainty in how
favorably timed the strongest ascent will be with peak
heating/destabilization and potential storm modes. These
uncertainties preclude probabilities at this time, but highlights
will likely be introduced as model consensus improves.

..Moore.. 03/27/2026

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ACUS48 KWNS 280858
SWOD48
SPC AC 280856

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0356 AM CDT Sat Mar 28 2026

Valid 311200Z - 051200Z

...DISCUSSION...
A return to a more seasonal upper-level regime will promote
strong/severe thunderstorm chances beginning D4/Tuesday and
potentially persisting into the upcoming weekend. A well-anticipated upper-level regime shift remains likely late this weekend and into
early next week as an upper ridge over the south-central CONUS
de-amplifies and shifts east. The return to mean troughing over the
West will promote persistent lee troughing and southerly return flow
into the Plains and lower MS Valley. Long-range guidance depicts
several upper disturbances propagating across the northern and
central U.S. through late week, which may each support some risk of strong/severe thunderstorms.

...D4/Tuesday...
A low-amplitude upper wave is forecast to traverse the U.S./Canadian
border and into the Great Lakes region Monday into Tuesday.
Northeastward moisture return ahead of an intensifying surface
cyclone and trailing cold front will likely establish a fairly broad
warm sector from the Ozarks into the Midwest/Great Lakes region.
Thunderstorm development along the cold front is expected by late
afternoon with most deterministic and ensemble guidance showing
strong QPF signals. Any severe weather threat will likely be focused
from central IL northeastward into northern IN/southern MI where
deep-layer wind shear will be stronger in proximity to the upper jet
and shear vectors should be more orthogonal to the front. While some
solutions depict favorable MLCAPE and shear for organized convection
(e.g. the 00z GFS), ensemble consensus shows muted probabilities for
a highly favorable convective environment (e.g. recent GEFS depicts
less than 20% probability for SCP values above 3). This suggests
that even though some severe threat will likely materialize,
considerable uncertainty remains regarding the quality of the
convective environment.

...D5/Wednesday and D6/Thursday...
Tuesday's cold front is expected to stall roughly along or south of
the OH River by the afternoon of D5/Wednesday. This will maintain a
moist warm sector across the southern Plains eastward to the TN
Valley. Strong to severe thunderstorm potential may emerge on
D5/Wednesday and D6/Thursday as an upper disturbance propagates
across the southern Plains and into the OH Valley and supports
ascent along and north of the stalled frontal zone. Given the
relatively focused nature of the wave and attendant mid-level jet,
widespread severe convection seems improbable, though a favorable buoyancy/shear environment is possible in the vicinity of the
stalled front each afternoon.

..Moore.. 03/28/2026

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ACUS48 KWNS 290846
SWOD48
SPC AC 290845

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0345 AM CDT Sun Mar 29 2026

Valid 011200Z - 061200Z

...DISCUSSION...
A more seasonal synoptic regime is expected over the CONUS through
the upcoming week as long-wave troughing slowly becomes established
over the western two-thirds of the country. This will favor lee
cyclone development and poleward moisture return ahead of occasional
frontal intrusions. In general, ensemble consensus is that a
leading, low-amplitude upper disturbance will propagate across the
central CONUS during the D4/Wednesday to D5/Thursday period before a
more amplified upper trough migrates into the Plains during the
D6/Friday to D7/Saturday time frame. While there is broad agreement
in this pattern among most guidance, notable discrepancies and
spread among solutions limits confidence in the location, timing, or
magnitude of any severe threat.

...D4/Wednesday - Southern Plains...
A cold front pushing east/southeast across the central U.S. on
Tuesday is forecast to stall across the southern Plains into the OH
Valley by Wednesday. Aloft, ascent associated with the leading upper disturbance will overspread TX/OK, leading to modest surface low
development along the stalled frontal boundary. Continued moisture
return coupled with easterly advection of steep mid-level lapse
rates will likely yield a reservoir of buoyancy across portions of central/eastern TX/OK and into AR/LA. Thunderstorm development along
the frontal zone appears probable by late afternoon, and 40-50 knot
mid-level flow attendant to the wave should provide adequate wind
shear for organized storms. However, guidance continues to show
variability with frontal placement and is likely displaying a
northward bias given the tendency for long-range guidance to
underestimate low-level cold advection. Additionally, it is unclear
whether storm motions and deep-layer shear vectors will be favorably
oriented to the front to support discrete convection and a more
robust severe threat.

...D6/Friday and D7/Saturday - Southern Plains to the Ohio Valley...
More intense surface low development is anticipated across the
southern Plains and Great Lakes region Friday into Saturday as an
more amplified upper wave begins to migrate east. Northward moisture
return will likely continue through Friday with thunderstorm
development possible in vicinity to the deepening lee cyclone.
Although model variability remains fairly high at this range,
ensemble guidance does show a modest QPF signal across OK/KS where
the probability for adequate SBCAPE and deep-layer shear for
organized convection is reasonably high.

On Saturday, the ejection of the upper wave into the Plains will
result in the northeastward acceleration of the lee cyclone. Rapid
moisture return within a strengthening low-level wind field is
possible as the low reaches the Great Lakes region by late Saturday.
Based on forecast soundings and ensemble QPF signals, some severe
thunderstorm potential is noted along and ahead of a cold front
attendant to the low. However, high variability among guidance over
the past 24 hours and the potential for a sub-optimal displacement
of the primary upper jet with the expanding warm sector casts
considerable uncertainty on the overall severe threat.

..Moore.. 03/29/2026

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ACUS48 KWNS 300855
SWOD48
SPC AC 300853

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0353 AM CDT Mon Mar 30 2026

Valid 021200Z - 071200Z

...DISCUSSION...
Severe thunderstorm potential is expected to persist through the
work week and into the upcoming weekend. Long-range guidance has
come into better agreement over the past 24 hours regarding the
evolution of the synoptic regime - particularly regarding the
progression of an upper level trough and attendant surface low
during the late-week/early-weekend period.

...D4/Thursday - Midwest/Ohio Valley...
A cold front pushing across the Midwest on Tuesday is forecast to
stall across the OH Valley on Wednesday before advancing northward
as a warm front ahead of an approaching surface low on Thursday.
Northward moisture return is expected ahead of a weak cold front
attendant to the low. Long-range forecast guidance suggests this
will support adequate buoyancy for deep convection, and 35-45 knot
deep-layer shear vectors will favor organized storms. Uncertainties
regarding storm mode persist based on mean wind vectors largely
parallel to the front, but some severe risk appears likely given
favorable buoyancy and shear.

...D5/Friday - Central/Southern Plains...
Ensemble consensus is that an amplified upper trough will begin to
approach the central Rockies/High Plains through the day Friday.
This will promote strong lee cyclogenesis across CO/KS and a
northward surge of moisture (potentially as high as low to mid 60s
dewpoints) into OK and eastern KS. Thunderstorm development in
proximity to the deepening low appears probable by late afternoon
based on deterministic and ensemble QPF signals, and strengthening
flow aloft may favor discrete storm modes for convection developing
along a sharpening dryline. Ensemble guidance, notably the 00z GEFS,
shows a fairly strong signal for a substantial convective
environment from northern OK into eastern KS Friday afternoon (e.g.
30% probability for SCP values above 5). Despite improving agreement
among deterministic and ensemble guidance, this alignment has only
emerged over the past 12-24 hours. Severe probabilities will likely
be needed for portions of eastern KS and northern OK if this trend
holds over the next 24 hours.

...D6/Saturday - Ohio Valley...
Similar to D5/Friday, guidance has come into better agreement
regarding the intensification and northeastward progression of the
surface low through D6/Saturday into the Great Lakes region. This
will usher moisture northward into the OH Valley by Saturday
afternoon where diurnal heating may support either development of
new convection along a trailing cold front and/or re-intensification
of residual convection (though the quality and extent of moisture
return remains somewhat uncertain at this range). Regardless,
intensifying wind fields should promote storm organization and the
potential for a more widespread severe weather event. As with
D5/Friday, risk probabilities will likely be needed if current model
trends are maintained and confidence the moisture/buoyancy quality
increases.

..Moore.. 03/30/2026

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ACUS48 KWNS 310852
SWOD48
SPC AC 310850

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0350 AM CDT Tue Mar 31 2026

Valid 031200Z - 081200Z

...DISCUSSION...
Severe weather potential will persist through the remainder of the
work week and into parts of the weekend as an amplified upper wave
and attendant surface low traverse the country. The cold front
associated with the late-week storm system will most likely push
south into the Gulf by Sunday as high pressure builds across the
eastern two-thirds of the country and short-wave ridging builds
aloft. This will likely limit the potential for widespread severe
thunderstorms for the early portion of next week.

...D4/Friday - Lower Missouri Valley into the southern Plains...
The approach of an upper wave into the central U.S. will support
steady intensification of a surface low across eastern KS and into
the lower MO River Valley through the day Friday. This will support
a northward flux of low to mid 60s dewpoints through the day, which
should yield SBCAPE values on the order of 2000 to perhaps 3000 J/kg
across northern OK into eastern KS and far western MO by late
afternoon based on a consensus of model solutions. Thunderstorm
development is expected as a cold front slowly begins to push
southeast and overtakes a surface trough/dryline. Deep-layer shear
vectors and storm motions off the boundary should promote initially
discrete cells, though upscale growth is anticipated by the evening
hours amid persistent ascent along the front. Regardless, long-range
guidance has shown a consistent signal for a robust convective
environment over the past 48 hours, and the favorable alignment of
both deterministic and ensemble guidance lends high confidence in a
severe threat emerging across this region Friday afternoon and
evening.

...D5/Saturday - Midwest/OH Valley...
Friday's surface low will continue to deepen as it accelerates
northeastward into the Midwest and Great Lakes by late Saturday.
Northward moisture advection is expected ahead of a trailing cold
front as it rapidly shifts east across the Midwest and lower OH
Valley through the afternoon. Strong flow fields within the lowest
few kilometers and focused lift along the front will likely support
some degree of a severe wind threat. However, guidance continues to
show disagreement regarding mean wind vector orientation with the
front and the degree of pre-frontal destabilization, both of which
will influence the intensity of convection and the overall severe
threat.

..Moore.. 03/31/2026

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ACUS48 KWNS 010829
SWOD48
SPC AC 010827

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0327 AM CDT Wed Apr 01 2026

Valid 041200Z - 091200Z

...DISCUSSION...
Some degree of severe thunderstorm potential is expected to persist
through the upcoming weekend across portions of the Great Lakes/OH
Valley and possibly across the Mid-Atlantic. Heading into next week,
a combination of building surface high pressure behind a synoptic
cold front and the re-establishment of an upper ridge over the West
will limit severe weather chances.

...D4/Saturday - Great Lakes/OH Valley...
An upper wave and attendant surface low are forecast to quickly
translate from the Plains into the Great Lakes region late Friday
through Saturday. Moisture return immediately ahead of a trailing
cold front will likely support some degree of destabilization
Saturday afternoon across the Great Lakes/OH Valley; however,
long-range ensemble guidance does not show high probability in surface/mixed-layer buoyancy values exceeding 1000 J/kg.
Nonetheless, strong flow within the lowest 1-2 km will likely
support a severe wind threat with any convection that can become
sufficiently intense. While some severe risk is anticipated, the
combination of a modest thermodynamic environment and disagreement
regarding the timing/progression of the front through peak heating
precludes risk probabilities.

...D5/Sunday - Mid-Atlantic...
The synoptic cold front is forecast to push off the East Coast by
late Sunday, though long-range guidance shows disagreement regarding
the timing of the front. Slower solutions, such as the 00z ECMWF,
suggest that the frontal passage may occur during the afternoon
hours when diurnal destabilization will be greatest. Strong
low-level flow coupled with robust broad-scale ascent ahead of the
primary upper wave may support a band of strong to severe
thunderstorms. However, the general consensus among guidance at this
time is that this scenario is likely the outlier solution.

..Moore.. 04/01/2026

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ACUS48 KWNS 020835
SWOD48
SPC AC 020833

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0333 AM CDT Thu Apr 02 2026

Valid 051200Z - 101200Z

...DISCUSSION...
Severe weather potential will be limited for late weekend and into
the upcoming work week based on trends in latest guidance. A strong
synoptic cold front is forecast to push from the Appalachians and
lower MS Valley east/southeastward towards the East Coast and
northern Gulf through the day Sunday. While some severe threat may
materialize across the Carolinas and Mid-Atlantic Sunday afternoon,
it will be conditional on favorable timing of the frontal passage
with the diurnal heating maximum. The frontal passage will shunt
appreciable low-level moisture offshore by early Monday. Building
surface high pressure over the central to eastern CONUS through
early week will maintain dry and stable conditions east of the
Rockies. Additionally, the amplification of an upper ridge over the
West will limit thunderstorm chances across the Intermountain West.
This synoptic regime will limit moisture return back into the Plains
with most guidance suggesting that appreciable moisture return (55+
dewpoints) may not return to the Plains until the D8/Thursday time
frame. Consequently, the potential for severe convection will be
limited through at least the middle of the upcoming week.

..Moore.. 04/02/2026

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ACUS48 KWNS 030822
SWOD48
SPC AC 030821

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0321 AM CDT Fri Apr 03 2026

Valid 061200Z - 111200Z

...DISCUSSION...
...Monday/Day 4 to Wednesday/Day 6...
From Monday to Wednesday, a relatively dry and cool airmass is
forecast to settle in across the continental U.S. For this reason,
thunderstorm potential will be low over most of the nation.

...Thursday/Day 7 to Friday/Day 8...
A large area of surface high pressure is forecast to move eastward
in the western Atlantic by Thursday, as moisture return takes place
into the south-central states. Scattered thunderstorm development
will be possible during the day from the southern and central Plains
eastward into the lower to mid Mississippi Valley. A chance for
thunderstorms will continue into Friday over the same general area
as moisture advection continues. An isolated severe threat will be
possible each afternoon and evening, but the confidence in the
spatial distribution regarding any potential threat is low at this
time.

..Broyles.. 04/03/2026

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ACUS48 KWNS 040846
SWOD48
SPC AC 040844

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0344 AM CDT Sat Apr 04 2026

Valid 071200Z - 121200Z

...DISCUSSION...
...Tuesday/Day 4 and Wednesday/Day 5...
A large area of surface high pressure will settle in across the
continental U.S. on Tuesday and Wednesday. The associated dry and
cool airmass will limit thunderstorm potential in most areas.

...Thursday/Day 6 to Saturday/Day 8...
On Thursday, a cold front is forecast to move southward into the
central Plains and stall, as moisture advection takes place to the
south of the front over much of the southern Plains. A dryline is
forecast to setup over west Texas Thursday afternoon. Thunderstorm
development will be likely along parts of the front and to the east
of the dryline. An isolated severe threat will be possible in the
afternoon and evening. Models differ considerably on the
distribution of instability, with some suggesting that instability
will remain relatively weak. This would keep any severe threat
marginal in most areas.

On Friday and Saturday, a moist and unstable airmass is forecast to
be in place over the southern half of Texas, as a shortwave trough
moves northeastward across the region. Lift associated with this
feature would support scattered thunderstorm development. The
greatest severe potential both Friday and Saturday appears to be
across south-central Texas, where the models have moderate
deep-layer shear and sufficient instability. At this extended range, uncertainty concerning magnitude and spacing is substantial.

..Broyles.. 04/04/2026

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ACUS48 KWNS 050850
SWOD48
SPC AC 050848

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0348 AM CDT Sun Apr 05 2026

Valid 081200Z - 131200Z

...DISCUSSION...
...Wednesday/Day 4 and Thursday/Day 5...
From Wednesday into Thursday, an upper-level trough will move from
the High Plains into the Great Lakes, as a large area of surface
high pressure moves across the eastern U.S. Along the western edge
of this feature on Thursday, low-level moisture advection is
forecast from the southern and central Plains into the lower to mid
Mississippi Valley. Within this returning airmass, isolated to
scattered thunderstorms will be possible Thursday afternoon and
evening. The best chance for severe storms would be across parts of
the central Plains, as the low-level jet ramps up in the evening.
Uncertainty exists concerning the magnitude of any potential severe
threat.

...Friday/Day 6 to Sunday/Day 8...
Moisture advection is forecast to continue on Friday over the
southern Plains and Ark-La-Tex, as surface dewpoints increase into
the 60s F. A slow-moving cold front is forecast to stall in the
central Plains, which would be a focus for thunderstorm development.
Isolated to scattered storms are also expected on Friday along and
to the east of a dryline in the southern High Plains. An isolated
severe threat would be possible in areas that sufficiently
destabilize. The potential for severe storms should continue into
Saturday and Sunday over the southern and central Plains, as an
upper-level trough moves across the region. At this time, model
spread is substantial concerning the magnitude and spatial
distribution of instability. The models also vary widely on the
timing and amplitude of the shortwave trough. For these reasons,
will hold off introducing a threat area until the models can show
better agreement.

..Broyles.. 04/05/2026

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ACUS48 KWNS 060835
SWOD48
SPC AC 060834

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0334 AM CDT Mon Apr 06 2026

Valid 091200Z - 141200Z

...DISCUSSION...
...Thursday/Day 4 to Saturday/Day 6...
From Thursday to Saturday, mid-level flow over the south-central
U.S. is forecast to gradually transition from westerly to
southwesterly. In response, low-level moisture advection will likely
take place in the southern and central Plains. Isolated severe
storms will be possible near a front in the central Plains from late
Thursday afternoon into the early overnight period, as a low-level
jet strengthens. On Friday, weak instability is forecast to develop
over much of the southern Plains. Isolated to scattered
thunderstorms will be possible in the afternoon and evening across
parts of this airmass. An isolated severe threat may develop in some
areas, but deep-layer shear is forecast to be relatively weak over
much of the southern Plains, suggesting a more localized severe
potential.

On Saturday, the potential for severe storms is expected to increase
over parts of southern High Plains, as mid-level southwesterly flow strengthens. Model consensus suggests that the greatest severe
threat potential will be over parts of west Texas, where some models
have an axis of moderate instability in place by late Saturday
afternoon. Supercells with large hail and severe wind gusts will be
possible in the afternoon and evening, with storms that develop near
this instability axis.

...Sunday/Day 7 and Monday/Day 8...
On Sunday, an upper-level low and an associated trough is forecast
to move eastward across the Desert Southwest and northern Mexico.
Ahead of this trough, moderate instability is forecast to develop by
Sunday afternoon over much of the southern High Plains. Scattered
severe storms would be possible to the east of a west Texas dryline
in the afternoon and evening. A severe threat should continue into
the overnight as a low-level jet strengthens ahead of the
approaching trough.

On Monday, the upper-level trough is forecast to move quickly
northeastward across the central U.S, with an axis of moisture and
instability located in the Great Plains. Scattered severe storms
will be possible from Monday into Monday night from the southern
Plains northward into Upper Midwest. At this extended range, there
is still considerable uncertainty concerning the timing of the
trough. For this reason, will hold off on a threat area until the
models show better agreement.

..Broyles.. 04/06/2026

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ACUS48 KWNS 070858
SWOD48
SPC AC 070856

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0356 AM CDT Tue Apr 07 2026

Valid 101200Z - 151200Z

...DISCUSSION...
...Friday/Day 4 to Sunday/Day 6...
An upper-level trough will move eastward from the eastern Pacific on
Friday into the western U.S. on Saturday, as southwest mid-level
flow gradually strengthens over the south-central states. In
response, low-level moisture advection will continue over the Great
Plains. Ahead of the western U.S. trough, a subtle shortwave trough
is forecast to move into the southern High Plains Saturday
afternoon. A severe threat will be possible ahead of and near the
trough during the afternoon and evening.

On Sunday, the western U.S. upper-level trough is forecast to move
quickly east-northeastward into the southern Rockies. Ahead of the
trough, a moist and moderately unstable airmass is forecast over
much of the southern and central Plains by afternoon. Scattered
thunderstorms appear likely to develop over much of this airmass
during the afternoon and evening. Moderate to strong deep-layer
shear appear likely to be in place, which will be favorable for
severe storms. Supercells with large hail, severe wind gusts and a
tornado threat will be possible. An isolated severe threat may also
develop in parts of the north-central U.S.

...Monday/Day 7 and Tuesday/Day 8...
A secondary upper-level trough is forecast to move into the Desert
Southwest on Monday. Ahead of this system, a moist and unstable
airmass is forecast to remain in place from the southern Plains north-northeastward into the Upper Midwest. Although a severe threat
will be possible along much of the instability corridor, the
greatest threat is expected to develop in the southern Plains, where
model forecasts show the most favorable environment.

On Tuesday, model forecasts have some agreement concerning the
timing of the trough, which is forecast to eject northeastward
across the southern and central Plains. Ahead of the trough, there
is large variance among the models concerning the distribution of
instability. If a moderately unstable airmass is in place by Tuesday
afternoon ahead of the ejecting system, a severe threat will be
likely from the southern Plains into the mid to upper Mississippi
Valley. However, the system will probably be slower than forecast,
which adds considerable uncertainty this late in the period.

..Broyles.. 04/07/2026

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