RSS Mesoscale Discussions from Storm Prediction Center
No watches are valid as of Thu Dec 4 00:29:02 UTC 2025.
No Mesoscale Discussions are in effect as of Thu Dec 4 00:29:02 UTC 2025.
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0149 PM CST Wed Dec 03 2025
Valid 032000Z - 041200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF
THE UPPER TX GULF COAST INTO FAR SOUTHWEST LOUISIANA...
...SUMMARY...
A stronger storm or two is possible along the upper Texas Gulf Coast
into the Sabine Valley. Marginally severe hail could occur.
...20Z Update...
No changes to the outlook are necessary. See the previous discussion
for additional details.
..Wendt.. 12/03/2025
.PREV DISCUSSION... /ISSUED 1017 AM CST Wed Dec 03 2025/
...Synopsis...
A mid-level wave traversing the Four Corners region as of
mid-morning is forecast to move eastward into the southern Plains
through early Thursday morning. West/southwesterly mid-level flow
will steadily increase to around 50-60 knots as the wave approaches,
which will help advect a plume of modestly steep (7 to 7.5 C/km)
lapse rates out of northern Mexico towards the TX/LA Gulf Coast
region through tonight. At the surface, a weak surface low noted off
the south TX coast will gradually intensify and lift northward
towards the LA coast as broad-scale ascent ahead of the upper wave
increases later tonight. The combination of increasing ascent and
steepening lapse rates will support isolated to scattered
thunderstorms tonight into early Thursday morning for much of the TX
Coastal Plain and central to southern LA.
...Upper TX Gulf Coast to far southwest LA...
Isolated to scattered thunderstorms are expected to develop along
the upper TX Gulf Coast around 02-04 UTC tonight as warm advection
atop a residual frontal boundary increases. Forecast consensus is
that the surface low will remain off the coast through the forecast
period, which will limit the potential for surface-based convection.
However, strong moistening/ascent within the 925-850 mb layer will
likely support a narrow swath of deep convection along the TX coast
where MUCAPE may exceed 1000 J/kg. Within this zone, buoyancy
profiles should be deep enough to realize the favorable kinematic
environment, which will be characterized by elongated hodographs and
effective shear of around 50 knots. Destructive storm
interactions/modes will likely modulate the overall longevity of any
particular cell, but the sufficient thermodynamic/kinematic
environment may support a few brief strong/severe storms capable of
small to severe hail.
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SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0344 PM CST Wed Dec 03 2025
Valid 051200Z - 111200Z
...Synopsis...
Longer term ensemble guidance suggests a large scale upper-level
troughing pattern should hold across the eastern U.S. through the
middle of next week. This should facilitate a mostly stable and
colder air mass across much of the eastern U.S., limiting the fire
weather threat. A mid-level jet and associated ascent in addition to
a frontal boundary meandering near the Gulf Coast should bring
several rounds of rain to much of the Deep South and Piedmont
regions, where severe/extreme drought lingers in portions of
southern GA/northern FL. Farther west, model guidance shows a
gradually expanding upper-level ridge across building into CA and
Desert Southwest through the weekend, allowing dry conditions and
above normal temperatures to develop. A short wave within the
broader northwest flow aloft translates southeastward into the
central/southern Rockies on Day 4/Saturday while a lee cyclone
evolves across the central/southern High Plains. Dry and breezy
conditions should develop across eastern NM and West TX on Day
4/Saturday but antecedent precipitation tonight into Day 2/Thursday,
including accumulating snowfall, should mitigate fire weather
impacts overall into the weekend. The Southern Plains will remain
the focus for fire weather concerns on Days 7-8/Tuesday-Wednesday
with potential lee cyclone/trough development along the
central/southern High Plains under robust northwest flow aloft.
However, uncertainty in fuels precludes introducing critical
probabilities at this time.
..Williams.. 12/03/2025
...Please see www.spc.noaa.gov/fire for graphic product...
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