ACUS01 KWNS 151258
SWODY1
SPC AC 151256

Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0656 AM CST Sat Feb 15 2025

Valid 151300Z - 161200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE LOWER MISSISSIPPI VALLEY...MID-SOUTH...AND SOUTHEAST...

...SUMMARY...
Severe thunderstorms are expected from parts of far east Texas into
much of the lower Mississippi Valley and Southeast. Several
tornadoes and scattered to numerous damaging wind gusts should be
the primary threats. A few strong tornadoes are also possible.
Intense thunderstorms should develop by late this afternoon and
continue through the overnight hours.

...East Texas into the Lower Mississippi Valley and Southeast...
Strong low-level warm advection has encouraged elevated
thunderstorms early this morning from parts of AR into the Mid-South
and TN Valley. This activity should remain sub-severe, with poor
mid-level lapse rates hindering updraft strength and hail potential.
A pronounced upper trough over the Southwest this morning will eject
eastward across the southern/central Plains today, eventually
reaching the MS/OH Valleys and Southeast late tonight. A broad area
of surface low pressure is forecast to consolidate through the day,
with the primary surface low expected to deepen as it develops east-northeastward across the Mid-South and lower OH Valley this
evening. An attendant cold front will eventually move
east-southeastward over the lower MS Valley and much of the
Southeast this evening and overnight.

Ahead of the approaching upper trough and deepening surface low,
low-level moisture will continue to stream northward across the
lower MS Valley. While lapse rates aloft should remain fairly
modest, filtered daytime heating and low-level moistening will aid
in the development of around 500-1000 J/kg of MLCAPE by mid to late
afternoon. Current expectations are for robust, surface-based
thunderstorms to develop by 20-22Z along or just ahead of the cold
front from far east TX towards the Mid-South. While this activity
may initially be supercellular, nearly all guidance suggests a quick
transition to a more linear mode by early evening. Even so, very
strong 0-3 km shear, aided by a 45-55+ kt low-level jet, will easily
aid updraft rotation and organized severe thunderstorms.

Ample low-level shear will support a threat for several
line-embedded tornadoes from late this afternoon through early
Sunday morning. The potential for supercells ahead of the line
remains unclear. But, any supercells embedded within the line could
produce strong tornadoes given the enhanced low-level shear.
Otherwise, scattered to numerous severe/damaging winds will likely
occur with the line of convection as it spreads eastward across the
Mid-South, TN Valley, and central Gulf Coast states this evening and
overnight. Isolated significant severe gusts appear possible where
the best overlap of strong low/mid-level flow and adequate buoyancy
is forecast, mainly across parts of the ArkLaMiss into western TN.
Some adjustments have been made to the Enhanced and Slight Risk
areas to account for latest guidance trends, including across parts
of AL/GA where a threat for tornadoes and damaging winds will likely
continue through the end of the period as the line advances eastward
in a weak but sufficiently unstable airmass.

..Gleason/Broyles.. 02/15/2025

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