ACUS03 KWNS 160728
SWODY3
SPC AC 160727
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0227 AM CDT Thu Oct 16 2025
Valid 181200Z - 191200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE ARK-LA-TEX...OZARKS AND MID MISSISSIPPI VALLEY...
...SUMMARY...
Severe thunderstorms will be possible on Saturday across parts of
the Ark-La-Tex, Ozarks and mid Mississippi Valley. A threat for
tornadoes, damaging wind gusts and hail is expected to develop from
the late morning into the overnight.
...Ark-La-Tex/Ozarks/Mid Mississippi Valley...
A large-scale mid-level trough will move across the Great Plains on
Saturday, as an associated jet streak moves into the Ozarks.
Scattered thunderstorms will likely be ongoing just ahead of the
trough at the start of the period, from eastern Oklahoma into
central Missouri. To the south and east of this activity, moderate
instability is expected to develop during the morning over much of
the Ark-La-Tex and Ozarks. As surface temperatures warm across the
moist sector, convective coverage is forecast to gradually increase.
An MCS appears likely to form during the afternoon, with a
relatively large cluster of storms moving eastward across southern
Missouri, Arkansas and northern Louisiana. The MCS is expected to
become organized and pose a severe threat across the region.
Ahead of the MCS, forecast soundings during the mid afternoon have
MLCAPE peaking between 1500 and 2000 J/kg, with 0-6 km shear in the
50 to 55 knot range. 0-3 km storm-relative helicity is forecast to
increase to about 250 m2/s2 near the low-level jet in the late
afternoon. This should support supercell development with tornado
potential. Storms that remain discrete and interact with the
low-level jet will have the greatest potential for tornadoes.
Supercells should also be capable of large hail. Once the MCS
becomes organized, a transition to linear mode could occur. If this
were to happen, then the wind-damage threat would increase, and
could become the greatest threat. Any severe threat should persist
through the evening, and possibly into the early overnight period,
as the MCS moves eastward across the central Gulf Coast states and
Tennessee Valley.
...Lower Ohio Valley/Southern Great Lakes...
A mid-level trough will move across the Great Plains on Saturday, as
a belt of southwesterly flow remains from the mid Mississippi Valley
into the Great Lakes. At the surface, a cold front will advance
southeastward across the mid to upper Mississippi Valley, and Great
Lakes region. A corridor of low-level moisture will be present ahead
of the front with surface dewpoints in the lower to mid 60s F. This
should allow for weak destabilization by afternoon. Thunderstorms
will develop along parts of the front, and move eastward into the
moist airmass. The models differ markedly on how much instability
will develop across this moist airmass, which adds considerable
uncertainty into the forecast. In spite of this, the combination of
instability and moderate deep-layer shear should be great enough for
an isolated severe threat. Line segments would be favored to produce
damaging wind gusts. A few rotating storms will also be possible.
..Broyles.. 10/16/2025
$$
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