RSS Mesoscale Discussions from Storm Prediction Center
No watches are valid as of Sat Nov 29 09:34:02 UTC 2025.
MD 2237 CONCERNING HEAVY SNOW FOR NORTHEAST/EAST-CENTRAL MO...SOUTHEAST IA...WESTERN IL
Mesoscale Discussion 2237
NWS Storm Prediction Center Norman OK
0318 AM CST Sat Nov 29 2025
Areas affected...Northeast/east-central MO...southeast IA...western
IL
Concerning...Heavy snow
Valid 290918Z - 291315Z
SUMMARY...Moderate to locally heavy snow rates are possible early
this morning.
DISCUSSION...A large precipitation shield is spreading across parts
of MO/IA and western IL early this morning, within the warm conveyor
region of a surface cyclone centered over southwest KS. Strong, deep
ascent being driven by both low-level warm advection and favorable
upper-level difluence will maintain widespread precipitation through
the early-morning hours.
Observations indicate that the surface freezing line (currently
draped from near/north of St. Louis into north-central/northwest MO)
generally delineates the transition between rain/mixed precipitation
and snow. Heavy snow has recently been observed at Kirksville (KIRK)
and Hannibal (KHAE) in northeast MO, with moderate snow observations
extending into southeast IA and western IL. Snow rates of near to
locally above 1 inch per hour may persist across these areas through
the pre-dawn hours.
Farther south into east-central MO, surface temperatures remain
near/above freezing with residual low-level dryness, but evaporative
cooling of the column should eventually allow for development of
moderate to locally heavy wet snow for a period of time this
morning. Precipitation intensity may support snow rates of
near/above 1 inch/hour and notable visibility reductions, though the
marginal surface temperatures could limit actual accumulation rates
to some extent. Later this morning (generally after sunrise), parts
of east-central MO may transition to mostly rain or mixed
precipitation, in response to persistent low-level warm advection.
..Dean.. 11/29/2025
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...ILX...LSX...DVN...DMX...EAX...
LAT...LON 38398984 38669113 39549204 40209267 41269249 41269153
40589027 39898960 39108933 38398984
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SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1148 PM CST Fri Nov 28 2025
Valid 291200Z - 301200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF
EAST/SOUTHEAST TEXAS INTO LOUISIANA...
...SUMMARY...
Isolated severe thunderstorms are possible across portions of east
and southeast Texas into western Louisiana today and tonight.
...Synopsis...
A broad upper trough and increasingly strong westerly flow over the
central US are forecast to quickly intensify today, moving into the
Ohio Valley by tonight. Accompanying the strengthening trough, a
surface low over OK will deepen and shift toward the mid MS valley.
Trailing the low, a strong cold front will sweep southeastward with
increasing moisture ahead of it over the far southern Plains. Ahead
of the front, isolated strong to severe storms are possible over
parts of East TX and western LA this afternoon into early Sunday
morning.
...Eastern Texas into western LA...
South of the surface low across parts of central and southeast TX,
low-level warm air advection is expected much of the day associated
with a weakening 850 mb low-level jet. Persistent southerly flow
will help transport low to mid 60s F dewpoints northward across the
TX coastal plain into portions of central TX and far western LA.
Filtered diurnal heating should allow for some warming of the
relatively cool boundary layer. This warming, along with the
increase in low-level moisture, should support at least weak
destabilization by peak heating as cold mid-level temperatures from
the approaching trough move overhead. While overall forcing and flow
aloft should be modest south of the primary upper trough, isolated
thunderstorms are possible within the warm advection regime through
the afternoon and into the evening/overnight hours.
Veering hodographs and a subtle increase in deep-layer shear should
favor some storm organization with convection across southeast TX
into far western LA. Wind fields will be weak, but slightly enlarged
low-level hodographs (ESRH 100-200 m2/s2) and a cellular storm mode
could favor transient supercell structures along with occasionally
organized multicells. A brief tornado and marginally severe hail are
possible with the stronger updrafts. While any sustained severe risk
is likely to be contingent upon sufficient warming for surface-base
buoyancy, at least a low-end risk is possible from late afternoon
through much of the overnight hours ahead of the cold front.
As the cold front moves south from the Red River into central TX
this afternoon and into the evening, additional storms are likely to
form along and behind it as the front encounters the northern
fringes of the moisture plume. Despite sufficient buoyancy (MLCAPE
500-1000 J/kg), the undercutting nature of the surging front should
tend to limit storm intensity. Still, sufficient deep-layer shear
(35-45 kt) could support a few stronger clusters as a broken line
develops and surges south. Isolated hail, and perhaps some strong
gusts are possible as the front is expected to quickly move toward
the coast and reach the Gulf early Sunday morning.
..Lyons/Weinman.. 11/29/2025
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SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1228 AM CST Sat Nov 29 2025
Valid 301200Z - 011200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
A few thunderstorms are possible along the Gulf Coast. Severe
thunderstorms are not expected.
...Synopsis...
A broad mid-level trough will traverse the Northeast as a second
mid-level trough to the west impinges on the Plains states tomorrow
(Saturday). This upper-air pattern will support surface high
pressure overspreading much of the CONUS, from the northern Rockies
to the Atlantic Coastline. However, on the southern periphery of
surface high pressure, a cold front will approach the Gulf Coast and
FL Peninsula through the first half of the period. Ahead of the
front, surface dewpoints in the mid 60s F will support enough
buoyancy for scattered thunderstorm development, given sufficient
lift due to low-level convergence along the cold front. A couple of
lightning flashes are possible over the central Rockies as a pocked
of cooler air aloft overspreads the region in tandem with the
passing mid-level trough. However, any scant buoyancy that develops
may only be adequate enough for lightning flashes that are too
sparse for the inclusion of thunder probabilities at this time.
..Squitieri.. 11/29/2025
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SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0219 AM CST Sat Nov 29 2025
Valid 011200Z - 021200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Scattered thunderstorms may develop along the Gulf Coast Monday into
early Tuesday morning. Severe thunderstorms are not currently
expected.
...Synopsis...
A mid-level trough will amplify over the central U.S. while rapidly
tracking eastward, encouraging surface high pressure to overspread
most of the CONUS on Day 3/Monday. As such, thunderstorm development
will be limited over most locales given static stability. However,
through the period, the eastward progression of the aforementioned
mid-level trough will encourage surface low development along the
eastern Gulf Coast. Low-level warm air advection ahead of the
developing low will allow low-level moisture to move inland by up to
a couple hundred miles, fostering enough buoyancy for scattered
thunderstorms. Thunderstorms may first develop along the TX/LA
coastlines during the day, with thunderstorms then developing over
southern MS to the northern FL Peninsula late Monday night into
early Tuesday morning. However, this buoyancy, which may be largely
elevated in nature, appears too scant to support organized severe
potential, with no severe probabilities introduced at this time.
..Squitieri.. 11/29/2025
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Day 4-8 Outlook
Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0330 AM CST Sat Nov 29 2025
Valid 021200Z - 071200Z
...DISCUSSION...
A broad mid-level trough will eject into the Atlantic while another
mid-level trough gradually progresses across the CONUS this upcoming
week into next weekend. A surface low will rapidly track from the
southeast Gulf Coast, northeastward along the Eastern Seaboard Day
4/Tuesday, supporting thunderstorm development along the Southeast
Coast and the FL Peninsula. Thereafter, surface high pressure and
associated static stability should limit thunderstorm development
over most locales until late in the week into the weekend. By this
point, moisture return across the western Gulf Coast region may
foster enough buoyancy to support thunderstorm potential. It is
plausible that strong to perhaps isolated severe thunderstorms may
develop over the TX Coastal Plain in the Days 6-7 (Thursday-Friday)
time frame if the moisture can become rich/deep enough to support
greater buoyancy. However, the lack in medium-range guidance
agreement lends too little confidence in this scenario for the
introduction of severe probabilities this far in advance.
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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0157 AM CST Sat Nov 29 2025
Valid 291200Z - 301200Z
...NO CRITICAL AREAS...
...Synopsis...
A midlevel trough and related surface cyclone will advance
east-northeastward from the central CONUS to the Great Lakes through
the period. A related cold front will move southward across the
southern Plains, with strong northerly surface winds in its wake.
However, a minimal overlap between the strongest post-frontal
surface winds and low RH will limit fire-weather concerns --
especially given recent and upcoming precipitation.
Farther east, dry/breezy return flow will develop across parts of
the Southeast in response to the evolving surface low. Around 10-15
mph sustained southeasterly surface winds and 25-35 percent RH may
yield locally elevated fire-weather conditions during the afternoon.
..Weinman.. 11/29/2025
...Please see www.spc.noaa.gov/fire for graphic product...
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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0158 AM CST Sat Nov 29 2025
Valid 301200Z - 011200Z
...NO CRITICAL AREAS...
...Synopsis...
Expansive surface ridging characterized by cool/cold surface
temperatures will limit fire-weather concerns across the CONUS on
Sunday.
..Weinman.. 11/29/2025
...Please see www.spc.noaa.gov/fire for graphic product...
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