653
ACUS48 KWNS 180926
SWOD48
SPC AC 180924

Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0324 AM CST Tue Nov 18 2025

Valid 211200Z - 261200Z

...DISCUSSION...
...Days 4-5/Fri-Sat - Southeast TX to the Carolinas...

A shortwave upper trough over the southern Plains will migrate east
across the Mid-South on Friday, and exiting the southern
Mid-Atlantic coast by Saturday evening. Gulf moisture will spread
across much of the region ahead of a weak surface low and slowly
moving cold front. Thunderstorms, perhaps some strong, could develop
near the front from southeast TX into the Mid-South and OH/TN Valley
vicinity on Friday into early Saturday. However, instability is
expected to remain weak as boundary layer moisture decreases with
northeast extent. Furthermore, low-level flow will remain veering
and boundary-parallel deep-layer flow will favor more of a
messy/training storm mode. While some low-end severe probabilities
could become necessary in later outlook, potential appears too low
for 15 percent probabilities on Friday.

Thunderstorms will continue to develop eastward into the Carolinas
on Saturday as the cold front continues to sag southeast. Weak
instability will likely preclude severe potential into Saturday.

...Days 6-8/Sun-Tue - Southern Plains...

Spread among forecast guidance increases considerably by Days
6-7/Sun-Mon and confidence/predictability is low. However, in
general another upper trough is expected to deepen across the
Southwestern U.S. early next week, perhaps ejecting into the Plains
sometime around the end of the forecast period. Gulf return flow
will occur across TX ahead of this next trough in a progressive
upper pattern. Increasing moisture and shear as the trough ejects
could support severe potential across the southern Plains early next
week, but details remain uncertain.

..Leitman.. 11/18/2025