No watches are valid as of Thu Nov 27 12:52:02 UTC 2025.MD 2235 CONCERNING HEAVY SNOW FOR PARTS OF CENTRAL UPPER MI INTO NORTHERN LOWER MI
Mesoscale Discussion 2235
NWS Storm Prediction Center Norman OK
0530 AM CST Thu Nov 27 2025
Areas affected...Parts of central Upper MI into northern Lower MI
Concerning...Heavy snow
Valid 271130Z - 271630Z
SUMMARY...Heavy lake-effect snow bands will continue through the
morning. Snow rates may approach or exceed 1-2 inches per hour on a
localized basis.
DISCUSSION...Cold cyclonic flow associated with a deep low over
western Quebec has generated several lake-effect snow bands over the
Great Lakes region. In particular, multiple snow bands are affecting
northern Lower MI this morning, with some apparent upstream
connection to bands across central Upper MI that are emanating from
Lake Superior. The KAPX and KMQT VWPs depict little change to the
low-level wind field over the last several hours, and guidance
generally suggests this northwesterly flow regime will remain
relatively unchanged through the remainder of the morning. This
should allow ongoing bands to persist, while some cooling aloft
(with 700 mb temperatures dropping to near/below -20 C) may
gradually increase snow-to-liquid ratios with time. Snow rates of
1-2 inches/hour (locally greater) will be possible within these
bands, especially if a dominant single band can develop. Wind gusts
of 30-45 mph combined with the locally heavy snow rates will result
in significant visibility reductions in and near the strongest
bands.
..Dean.. 11/27/2025
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...APX...MQT...
LAT...LON 46488655 46088599 45348492 44758394 44358393 44148417
44248498 45268623 46238709 46538710 46488655
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0647 AM CST Thu Nov 27 2025
Valid 271300Z - 281200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Severe storms are not anticipated today.
...FL...
A large upper trough remains dominant over the eastern U.S. today,
with a cold front sweeping southward across FL. A few thunderstorms
will be possible over central/south FL through the afternoon, but
low-level drying will eventually stabilize the air mass and end the
convective threat after dark.
...PA/NY...
Cold temperatures aloft and warm lake temperatures could be
sufficient for a few lightning strikes in the lee of Lake Erie and
Ontario today. Forecast soundings suggest mid-level lapse rates and
the depth of the unstable layer will be sufficient for occasional
thundersnow through today and this evening.
..Hart/Dean.. 11/27/2025
SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0228 AM CST Thu Nov 27 2025
Valid 291200Z - 301200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS
OF THE TEXAS COASTAL PLAIN TO THE SABINE RIVER VALLEY...
...SUMMARY...
Isolated severe thunderstorms are possible across portions of
southeast Texas into northern Louisiana Saturday afternoon or
evening.
...Synopsis...
A surface low will translate northeast from the southern Plains
toward the Great lakes as a broad mid-level trough overspreads the
central U.S. on Saturday. Relatively rich low-level moisture return
will occur across the Sabine River Valley ahead of a surface cold
front. Isolated to scattered thunderstorm development should occur
within a warm-air advection regime. Given strong vertical wind shear
in place due to a departing low-level jet, isolated strong to severe
storms are possible across the TX Coastal Plain toward the Sabine
River Valley ahead of the approaching cold front.
...Southeast Texas into northern Louisiana...
Scattered showers and thunderstorms will be ongoing across the
southern Plains into the Lower MS Valley within the warm-air
advection regime. Through the day, airmass modification will result
in some boundary layer destabilization as cloudiness and
precipitation gradually clears the warm sector over southeastern TX.
Over 1000 J/kg MLCAPE may materialize if surface temperatures can
exceed 70 F given expected mid to upper 60s F dewpoints beneath 7-8
C/km mid-level lapse rates. A surface cold front will sweep
southeastward toward eastern TX. However, the mid-level trough
should pivot northeastward through the day. As such, the surface low
and accompanying low-level jet are poised to depart the southern
Plains and track away from the axis of greater moisture and
instability, which should limit severe potential to some degree.
Still, low-level convergence along the cold front should support
thunderstorm development by afternoon peak heating across the TX
coastal plain to the Sabine River Valley. Strong enough flow along
the western periphery of the departing low-level jet, beneath modest
westerlies, will support elongated hodographs and over 30 kts of
effective bulk shear. Given the aforementioned buoyancy, multicells
and perhaps a couple of supercells are possible. Isolated severe
gusts/hail are possible, and a tornado cannot be ruled out.
..Squitieri.. 11/27/2025
Day 4-8 Outlook
Day 4-8 Convective Outlook
NWS Storm Prediction Center Norman OK
0353 AM CST Thu Nov 27 2025
Valid 301200Z - 051200Z
...DISCUSSION...
A progressive upper pattern will overspread the CONUS next week,
ushering in multiple rounds of surface high pressure across the
western, northern, and eastern CONUS. Thunderstorm development
should thus be limited over much of the U.S. through the extended
forecast period. One exception may be portions of the Gulf Coast
early next week. By around Day 6 (Tuesday), medium-range guidance
depicts a pronounced mid-level trough amplifying over the Middle MS
Valley, supporting surface low development along the southeast Gulf
Coast. Seasonal low-level moisture may advect a few hundred miles
inland from the coast, ahead of the surface low. If this occurs,
isolated severe thunderstorms may develop along the warm front.
However, timing and placement of the surface low differs too much
among medium range guidance for the introduction of severe
probabilities this far in advance.
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