ACUS03 KWNS 101914
SWODY3
SPC AC 101913

Day 3 Convective Outlook  
NWS Storm Prediction Center Norman OK
0213 PM CDT Tue Sep 10 2024

Valid 121200Z - 131200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF
THE SOUTHEAST...AND FROM EASTERN MONTANA INTO THE FAR WESTERN
DAKOTAS...

...SUMMARY...
A low-probability tornado threat may persist into Thursday across
parts of the Deep South. Isolated large hail and severe gusts will
be possible over the northern High Plains vicinity on Thursday
afternoon and evening.

...Synopsis...
An upper trough over the Great Basin will eject northeastward into
the northern Rockies/High Plains through Friday morning, with
moderate midlevel meridional flow aloft. Accompanying this trough
will be a cold front which will extend from eastern MT into eastern
WY. 

To the east, TC Francine is forecast to move northward up the lower
MS valley, with strong southerly winds helping to bring moisture
north across much of the Southeast east of the center/low. High
pressure will remain over the Mid Atlantic, adding to the pressure
gradient east of the cyclone.

...Eastern MT into the western Dakotas...
Daytime heating as well as cooling aloft with the upper trough will
result in steepening lapse rates, though low-level moisture will be
meager with 40s dewpoints primarily east of the cold front. A narrow
band of uncapped and unstable air will still develop during the late
afternoon, with around 1000 J/kg MUCAPE and 40 kt deep-layer
effective shear. As such, scattered cells are likely to develop
along the front, and the elongated hodographs may favor a few single
cells despite linear forcing mechanism. Therefore isolated hail over
1.00" may occur, as well as brief bowing segments producing strong
gusts.

...Much of AL, eastern MS...FL Panhandle...
Scattered thunderstorms are likely to exist from the northeastern
quadrant of TC Francine arcing southeastward across much of AL and
into the FL Panhandle Thursday morning. Low-level theta-e advection
will exist near a warm front as it lifts north across AL, though dry
air will exist from the Appalachians into parts of the OH/TN Valleys
initially.

The greatest risk of a couple tornadoes will likely be limited to
storms within the instability plume centered over AL, and including
the FL Panhandle and perhaps far eastern MS. Low-level shear will be
strong to start the day, but will be reduced as the system continues
north and low-level flow veers.

..Jewell.. 09/10/2024

$$