RSS Mesoscale Discussions from Storm Prediction Center
No watches are valid as of Sat Nov 29 23:16:02 UTC 2025.
MD 2240 CONCERNING HEAVY SNOW FOR PARTS OF THE MIDWEST
Mesoscale Discussion 2240
NWS Storm Prediction Center Norman OK
0216 PM CST Sat Nov 29 2025
Areas affected...parts of the Midwest
Concerning...Heavy snow
Valid 292016Z - 300015Z
SUMMARY...Bursts of moderate to heavy snow are most likely to evolve
east/northeast from central Illinois across parts of
central/northern Indiana towards the Michigan/Ohio border into this
evening. Snowfall rates around 1 inch per hour are probable, briefly
near 2 inches per hour possible, before waning tonight.
DISCUSSION...Within a broad swath of snow across parts of the
Midwest, bursts of moderate to heavy intensity appear likely to
persist north of the mixed-phase region centered on southern IL.
This has been accompanied by early-afternoon lightning flashes in a
confined corridor into central IL. With the dendritic growth zone
centered around 550 mb, mid-level ascent is largely progged to be
stronger eastward within the mixed-phase precip swath closer to the
OH Valley. Bulk of guidance suggests ascent will wane after sunset
farther north as the leading shortwave impulse dampens. Until that
occurs, snowfall reduced visibilities from a quarter to half-mile
per Springfield, Lincoln, Decatur, and Champaign IL observations
should shift northeastward. This setup should support initial
snowfall rates of 1-2 in/hr, becoming more localized near 1 in/hr
later.
..Grams.. 11/29/2025
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...IWX...IND...LOT...ILX...
LAT...LON 40028869 40628774 41928549 42018475 41478432 40868466
39578615 39288769 39498839 40028869
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SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0149 PM CST Sat Nov 29 2025
Valid 292000Z - 301200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF EASTERN TEXAS INTO WESTERN LOUISIANA...
...SUMMARY...
Isolated severe thunderstorms are possible across portions of east
and southeast Texas into western Louisiana through tonight.
...20z Update...
The previous forecast largely remains on track with only minor
adjustments required - mainly removal of thunder probabilities
across portions of OK/KS/MO where the mid-level vorticity maximum
and surface cold front have already passed through. Across
east/southeast TX, modest low-level moisture advection continues
northward with temperatures warming into the upper 70s and low 80s
for a few locations - a few degrees warmer than anticipated by
high-res guidance. This additional heating combined with persistent,
but shallow, convective showers across southeast TX lend confidence
that at least a few attempts at deeper convection are likely by peak
heating in the coming hours. Any appreciable tornado threat will
likely be limited to near/along a diffuse warm frontal zone draped
roughly from the Houston to Waco, TX area where low-level winds
remain south/southeasterly. Further north near the DFW metro,
deepening cumulus is noted in visible imagery where the surface cold
front is impinging on the northern extent of appreciable MLCAPE.
Thunderstorm development along the front appears likely in the
coming hours, but the modest buoyancy profiles should modulate
convective intensity. See the previous discussion for additional
details.
..Moore.. 11/29/2025
.PREV DISCUSSION... /ISSUED 1024 AM CST Sat Nov 29 2025/
...Central/East/Southeast Texas into Western Louisiana...
A mid-level shortwave trough over the Plains this morning will
continue to progress quickly east-northeastward today across the mid
MS Valley/Midwest and OH Valley. A related surface low over eastern
KS will likewise develop northeastward towards IL by this evening,
with an attendant cold front sweeping south-southeastward across
OK/TX and the ArkLaTex through tonight. Low-level warm/moist
advection will continue to aid the northward transport of a
partially modified Gulf airmass over portions of central/east TX and
perhaps western LA. Thunderstorms should eventually develop by late
afternoon/early evening along the front across north-central TX and
vicinity, even though large-scale ascent will remain nebulous behind
the departing mid-level shortwave trough.
Filtered daytime heating will result in modest destabilization
across the warm sector today, although mid-level lapse rates are not
expected to remain modest. Sufficient deep-layer shear associated
with a subtropical/southern branch of a mid/upper-level jet should
support some updraft organization. Hail and strong/gusty winds may
occur with the stronger cores that can develop and be sustained.
But, the surging cold front will likely undercut convection fairly
quickly. There also appears to be some chance for isolated
thunderstorms to develop ahead of the front from parts of central
into southeast TX late this afternoon. The large-scale forcing for
ascent with southward extent will remain weak/nebulous at best, but
low-level confluence may aid in convective initiation across this
area. If these thunderstorms can develop, they would have access to
greater instability and sufficient low-level shear to pose some
threat for a tornado or two. However, the overall environment still
supports maintaining a Marginal Risk given the departing shortwave
trough and related large-scale forcing, modest lapse rates aloft,
and tendency for the low-level flow to gradually weaken/veer with
time through this evening and tonight.
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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0133 PM CST Sat Nov 29 2025
Valid 301200Z - 011200Z
...NO CRITICAL AREAS...
No changes are needed to the D2 Fire Weather Outlook. See previous
text below.
..Thornton.. 11/29/2025
.PREV DISCUSSION... /ISSUED 0158 AM CST Sat Nov 29 2025/
...Synopsis...
Expansive surface ridging characterized by cool/cold surface
temperatures will limit fire-weather concerns across the CONUS on
Sunday.
...Please see www.spc.noaa.gov/fire for graphic product...
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SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0348 PM CST Sat Nov 29 2025
Valid 011200Z - 071200Z
Fire concerns are expected to remain low for the D3/Monday through
D8/Saturday period. A series of troughs will bring cool and wet
conditions across much of the CONUS. Less rainfall is expected
across portions of the Southern High Plains. Some episodic overlap
of windy/dry conditions may occur, particularly across the Texas and
Oklahoma Panhandles into western Texas. However, confidence in the
magnitude remains low. Periods of enhanced windy/dry conditions will
also be possible across portions of Southern California, with
periods of offshore flow behind storm systems. Overall, fuels in
these regions remain fairly wet from recent heavy rainfall which
should negate any fire weather concerns.
..Thornton.. 11/29/2025
...Please see www.spc.noaa.gov/fire for graphic product...
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