Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0258 PM CDT Wed Sep 24 2025
Valid 242000Z - 251200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM SOUTHERN
AND SOUTHEAST TX NORTHEASTWARD TOWARD THE TENNESSEE AND LOWER OHIO
VALLEYS...
...SUMMARY...
Isolated damaging wind gusts remain possible from parts of the
Mid-South/Tennessee Valley to south Texas.
...Southern TX...Lower MS Valley into TN/Lower OH Valleys...
Widely scattered thunderstorms persist this afternoon from parts of
southern and eastern TX across the lower MS Valley and toward the TN
Valley. An earlier complex of storms resulted in wind damage over
northwest LA, but has since weakened as it moved into southeast AR.
Instability is currently maximized near and south of a front from
south-central TX into LA and central MS where MLCAPE has risen into
the 2000-2500 J/kg range. Modest midlevel westerlies extend south
into AR/LA/MS, supporting faster storm motions. While deep-layer
shear is only 25-30 kt, the stronger mean wind speeds may support
stronger outflows with a few damaging gusts through the afternoon.
Farther north into western TN and KY, pockets of heating are noted
on visible imagery, and cells are beginning to form. While stronger
high level winds are noted, overall midlevel wind speeds remain
marginal. Given less instability with MLCAPE of 750-1000 J/kg, cells
may not be particularly severe, but still may support locally strong
gusts.
To the south, storms are likely to increase along the TX Coast late
this afternoon as the cold front continues south into the
instability axis, with localized strong winds as storms spread
south/east along with the boundary.
..Jewell.. 09/24/2025
.PREV DISCUSSION... /ISSUED 1129 AM CDT Wed Sep 24 2025/
...Mid-South/Tennessee Valley to South Texas...
Showers and thunderstorms are currently ongoing from the TX Hill
Country northeastward into the Mid-South. Thunderstorms from
northeast TX southwestward are largely behind an outflow-augmented
cold front that extends from south of JCT northeastward to a weak
low over the TXK vicinity. The undercutting character of this front
will likely continue throughout the morning, but modest heating of
the warm and moist airmass downstream from south-central TX into
northern/central LA and central MS will result in moderate buoyancy.
This should result in a trend toward a more surface-based storm
character this afternoon. Much of this region will be displaced
south of the stronger mid-level flow forecast to extend throughout
the base of the shortwave trough moving across OK. This displacement
should limit the overlap between the stronger buoyancy to the south
and the stronger shear to north, resulting in a largely
multicellular storm mode. This should temper updraft duration and
keep the overall severe potential isolated.
There will be slightly better overlap between the buoyancy and shear
from northeast LA into central MS, with this flow oriented a bit
more orthogonal to the boundary as well. This could lead to more
storm organization and the development of more coherent linear
structures capable of isolated damaging gusts. Even so, lapse rates
will remain poor and the overall intensity of these storms is
forecast to be modest.
Areas along the front from southern AR northward may struggle to
destabilize this afternoon, with only weak instability forecast by
most guidance. Even so, stronger large-scale forcing for ascent is
anticipated across this region as the shortwave trough currently
over OK continues eastward and trends towards a less positive, more
neutral tilt. This large-scale ascent will augment lift along the
front and near the surface low to support thunderstorms. Modest
buoyancy should temper updraft strength, but increasing mid-level
flow attendant to the approaching shortwave may foster occasional
updraft organization. Damaging wind gusts are possible if stronger
convection can be sustained, but a largely multicellular storm mode
should mitigate the overall severe potential.
Read more CHECK UPDATE ZOOM GRAPHIC
http://dlvr.it/TNGvp2
