RSS Mesoscale Discussions from Storm Prediction Center
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1105 AM CDT Sun Mar 23 2025
Valid 231630Z - 241200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EAST-CENTRAL
TEXAS INTO THE LOWER MISSISSIPPI VALLEY AND MID-SOUTH...
...SUMMARY...
Scattered severe thunderstorms are possible this afternoon and
evening from East Texas into the Lower Mississippi and Tennessee
Valleys. Large hail and damaging gusts are the main hazards, but a
couple of tornadoes could also occur.
...Lower MS Valley...
A strong upper trough is passing across the Midwest states today,
with a 90+ knot mid level jet over IL. To the south of this
feature, southwesterly low-level winds are transporting Gulf
moisture northward, with 60s dewpoints now into southeast AR. As
continued daytime heating/mixing and moisture advection occur,
sufficient destabilization will result in scattered thunderstorm
development by mid afternoon across eastern AR/west TN/western KY.
These storms will be in an environment of moderately-steep mid-level
lapse rates and CAPE of 1500-2000 J/kg. Strong deep-layer shear
will promote rotating storms, but veered and slowly weakening
low-level winds suggest that large hail and damaging wind gusts are
the primary concern. Storms will track eastward into middle TN by
early evening, while building southward into parts of LA/MS.
Progressively more moist/unstable air farther south may aid a
greater concern for a few tornadoes during the evening. Activity is
expected to affect parts of northeast AL before weakening in the
03-05z period.
...East TX...
Latest surface analysis shows a cold front pushing into
north-central TX. This boundary will continue southward through the
day, with strong heating and ample low-level moisture in the warm
sector to the south of the front. CAM solutions are in strong
agreement that scattered thunderstorms will form along and south of
the front by early evening. Forecast soundings show sufficient
vertical shear for organized/supercell storms capable of large hail.
..Hart/Wendt.. 03/23/2025
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SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1207 PM CDT Sun Mar 23 2025
Valid 241200Z - 251200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM SOUTHEAST
LOUISIANA INTO SOUTHWEST GEORGIA AND THE FLORIDA PANHANDLE...
...SUMMARY...
A few strong/possibly severe thunderstorms will be possible Monday
morning and afternoon, from southern Louisiana eastward to southern
Georgia and the Florida Panhandle.
...Synopsis...
An amplified upper pattern is forecast across the CONUS on Monday,
with an upper trough pivoting over the eastern U.S. while an upper
ridge builds across the West. A surface cold front is forecast to
extend from the central Appalachians southwest into southern
MS/AL/LA, and then westward into south-central TX by midday. This
front will shift south and east offshore the Atlantic coast into
north FL and the northern Gulf by evening, while the TX portion of
the front retreats northward during the afternoon and overnight
period as a warm front.
...Southeast LA into southwest GA and the FL Panhandle...
Morning thunderstorms are likely to be ongoing across the central
Gulf coast vicinity into southwest GA and the FL Panhandle ahead of
the main surface cold front. Stronger storms may be capable of
marginal hail or gusty winds with this initial activity. Another
round of thunderstorms may develop during the afternoon along the
cold front, depending on degree of heating and airmass recovery in
the wake of morning convection. Deep-layer westerly flow will be
modest, but increasing speed with height will produce
elongated/straight hodographs. Furthermore, cool temperatures aloft
(near -15 C at 500 mb) will support midlevel lapse rates near 7
C/km, and potential MLCAPE values up to 1000-1500 J/kg. This
suggests any afternoon convection that develops could pose a risk
for hail.
...TX Hill Country/Edward Plateau vicinity...
A conditional severe thunderstorm risk (hail/strong gusts) could
exist Monday afternoon if thunderstorms can develop. Low-level
moisture will increase as a surface warm front lifts north across
the region. However, large-scale ascent will be nebulous at best
with no appreciable height falls or shortwave impulses noted across
the area. Deep-layer flow also will remain weak. Nevertheless, some
CAMs guidance depicts a couple of storms developing during the
afternoon/early evening in weak upslope flow. However, NAM and RAP
soundings suggest weak capping from 850-700 mb. Coupled with
negligible large-scale ascent, this could very well suppress
convective development. However, cold temperatures aloft and steep
midlevel lapse rates will support sizable instability (MLCAPE near
2000 J/kg). Furthermore, strong heating into the 80s F will result
in a deeply mixed boundary layer. If a storm can develop, some
potential for isolated hail and gusty winds would be possible. The
overall risk appears too limited/conditional to include severe
probabilities at this time.
..Leitman.. 03/23/2025
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