178
ACUS01 KWNS 141630
SWODY1
SPC AC 141628

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1128 AM CDT Sat Sep 14 2024

Valid 141630Z - 151200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE NORTHERN/CENTRAL PLAINS...

...SUMMARY...
Thunderstorms capable of producing isolated severe gusts and hail
will be possible over parts of the north-central Plains this
afternoon and evening.

...Northern/Central Plains...
Modest ascent associated with a weak shortwave trough over eastern
WY is encouraging towering cu and recent thunderstorm initiation
across parts of western/central NE late this morning. This
convective development is also occurring along/near a weak surface
trough. Even though large-scale ascent is expected to remain fairly
modest across much of the northern/central Plains today in the wake
of a more prominent upper trough moving northeastward over central
Canada, most guidance still shows potential for isolated to
scattered thunderstorms developing this afternoon across parts of
northwest NE into western/central SD along/near the surface trough.
With modest/shallow low-level moisture in place, but steep mid-level
lapse rates per 12Z LBF/UNR soundings, robust daytime heating will
likely support around 1000-2000 J/kg of MLCAPE by mid afternoon.

West-southwesterly flow at mid levels is forecast to be only
modestly enhanced by the passing shortwave trough. Still, a veering
and gradually strengthening wind profile with height through mid
levels should support around 25-35 kt of deep-layer shear.
Occasional hail may occur with any marginal supercells that can
initially develop, although tendency for clustering and outflow
interactions may lead to an isolated severe wind threat with time
late this afternoon and early evening. The overall severe risk
should quickly wane this evening with the loss of daytime heating.

...Southern High Plains...
At least isolated high-based thunderstorms should develop this
afternoon across parts of the TX Panhandle and vicinity along/east
of a weak surface front/trough. With a deeply mixed boundary layer
expected with daytime heating, occasional strong/gusty downdraft
winds may occur with the more robust cores. However, weak deep-layer
shear should keep the overall severe wind threat rather isolated.

...East Texas into Southern Louisiana/Mississippi...
Isolated to widely scattered thunderstorms may develop along a weak
front from parts of east TX into southern LA/MS later this
afternoon. This activity would occur on the back side of a remnant
mid-level circulation over the Mid-South. While modestly enhanced
mid-level flow will be present, the potential for a more organized
severe wind threat appears too low to include probabilities at this
time.

..Gleason/Dean.. 09/14/2024

$$