RSS Mesoscale Discussions from Storm Prediction Center
No watches are valid as of Thu Nov 27 19:44:02 UTC 2025.
MD 2236 CONCERNING HEAVY SNOW FOR NORTHERN LOWER MICHIGAN
Mesoscale Discussion 2236
NWS Storm Prediction Center Norman OK
1100 AM CST Thu Nov 27 2025
Areas affected...Northern Lower Michigan
Concerning...Heavy snow
Valid 271700Z - 272200Z
SUMMARY...Snowfall rates of 1-2 inch per hour remain possible
through mid/late afternoon.
DISCUSSION...A dominant snow band off of Lake Michigan, with
upstream connection to Lake Superior, continues early this afternoon
in northern Lower Michigan. Dual-pol data from KAPX shows higher KDP
values within this band suggesting 1-2 inch per hour snowfall rates
are possible. Given limited change in the large-scale environment
over the next few hours, this band is expected to persist through
the afternoon. High-resolution ensemble guidance suggests this as
well. The most intense snowfall rates will likely being to wane by
late afternoon as mid-level ascent from a shortwave trough moves
away from the region. As this occurs, there may be a slight
southward wobble in the band as 850-700 mb winds subtly take on a
more northerly component.
..Wendt.. 11/27/2025
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...APX...
LAT...LON 44358438 44878534 45088560 45208556 45458547 44668384
44298383 44358438
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SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1020 AM CST Thu Nov 27 2025
Valid 271630Z - 281200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Organized severe thunderstorms are not forecast through tonight.
...Synopsis and Discussion...
A large-scale upper trough encompassing much of the central/eastern
CONUS will develop slowly eastward through the period. Isolated
thunderstorm potential today will generally remain limited to parts
of south FL and the Keys along/ahead of a southward-moving cold
front. 11/12Z soundings from XMR/TBW/KEY show southwesterly winds
strengthening with height at mid/upper levels. While sufficient
deep-layer shear may exist to support a stronger thunderstorm or two
this afternoon, especially along the Atlantic Coast in south FL, the
presence of poor mid-level lapse rates and weak low-level winds
should hinder the risk for organized severe thunderstorms over land.
Isolated lightning flashes may also occur with snow bands occurring
in western NY off of Lake Ontario.
..Gleason/Wendt.. 11/27/2025
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SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0139 PM CST Thu Nov 27 2025
Valid 272000Z - 281200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Organized severe thunderstorms are not forecast through tonight.
...20z Update...
Only minor adjustments were made to the thunder line to account for
ongoing trends across the Florida peninsula. Otherwise, no
additional changes are needed. See previous discussion for more
information.
..Thornton.. 11/27/2025
.PREV DISCUSSION... /ISSUED 1020 AM CST Thu Nov 27 2025/
...Synopsis and Discussion...
A large-scale upper trough encompassing much of the central/eastern
CONUS will develop slowly eastward through the period. Isolated
thunderstorm potential today will generally remain limited to parts
of south FL and the Keys along/ahead of a southward-moving cold
front. 11/12Z soundings from XMR/TBW/KEY show southwesterly winds
strengthening with height at mid/upper levels. While sufficient
deep-layer shear may exist to support a stronger thunderstorm or two
this afternoon, especially along the Atlantic Coast in south FL, the
presence of poor mid-level lapse rates and weak low-level winds
should hinder the risk for organized severe thunderstorms over land.
Isolated lightning flashes may also occur with snow bands occurring
in western NY off of Lake Ontario.
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SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1120 AM CST Thu Nov 27 2025
Valid 281200Z - 291200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
A few thunderstorms are possible over the southern Plains and lower
Missouri Valley Friday night into early Saturday morning. Severe
thunderstorms are not currently expected.
...Synopsis...
Mid-level ridging over the central US will shift eastward behind a
departing trough over the East. A second trough will deepen over the
Rockies encouraging lee cyclogenesis over the southern Plains
Friday. As the surface low deepens, modest low-level moisture will
advect northward with a 40-60 kt southerly low-level jet. Lift from
the approaching trough and an attendant cold front will support
isolated thunderstorms from the southern Plains to the lower MO
Valley late Friday into early Saturday.
...Southern Plains into the lower Missouri Valley...
Ahead of the lee low, strong low-level warm air advection will
transport middling surface moisture northward over parts of
central/north TX into southern OK ahead of the surging cold front.
In the wake of the prior frontal passage, a persistent surface
stable layer is likely to prevent substantial northward moisture
return over the southern Plains. However, cold mid-level
temperatures (H5 temps -24C) beneath the deepening upper trough will
likely support some elevated buoyancy development late Friday,
overnight into Saturday. Isolated thunderstorms are possible within
the boarder warm advection band. While generally weak, (~250-500
J/kg MUCAPE) sufficient destabilization and strong flow aloft could
support an occasional stronger storm capable of small hail from
northeast TX into eastern OK and the Ozarks. But, given the limited
thermodynamics, a sustained severe risk appears unlikely.
..Lyons.. 11/27/2025
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SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0130 PM CST Thu Nov 27 2025
Valid 291200Z - 301200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS PORTIONS OF
EASTERN TEXAS AND SOUTHWESTERN LOUISIANA...
...SUMMARY...
Isolated severe thunderstorms are possible across portions of
southeast Texas into western Louisiana Saturday afternoon or
evening.
...Synopsis...
The shortwave trough over the central Plains will move eastward as
mid-level westerly flow intensifies from the Plains to the MS Valley
and Midwest Saturday/Sunday. A surface low attendant to the trough
will move from OK/KS to the southern Great Lakes as a strong cold
front moves south from the Red River to the lower MS Valley.
Moisture return ahead of the front will support scattered
thunderstorms across eastern TX, the Sabine Valley and lower MS
valley through early morning Sunday.
...Southeast TX to western LA...
With southerly surface flow expected to develop ahead of the
deepening surface cyclone over the Plains Saturday, low-level
moisture advection should increase across coastal and southeast TX
into LA. A warm front will slowly lift northward, stalling over
southwest LA as it encounters a deep and cool air mass farther
north. Continued low-level warm air advection (despite ongoing
showers and remnant clouds) should allow for gradual destabilization
Saturday afternoon. While overall forcing for ascent appears weak as
the upper trough departs to the north, scattered thunderstorm
development appears probable, both within the low-level warm
advection regime and along the approaching cold front from the
Northwest. Given expected mid to upper 60s F dewpoints beneath 7-8
C/km mid-level lapse rates, around 1000 J/kg MLCAPE could support a
few stronger updrafts late Saturday through Sunday morning. Residual
westerly flow aloft may also favor some storm organization with
multicell lines or clusters and perhaps transient supercells capable
of damaging gusts and hail. This is most likely from the TX coastal
Plain to southwestern LA before the cold front moves offshore into
the Gulf.
..Lyons.. 11/27/2025
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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook
NWS Storm Prediction Center Norman OK
0934 AM CST Thu Nov 27 2025
Valid 271700Z - 281200Z
A slight expansion west and north was made to the Elevated area
based on the latest observations and high-resolution forecast
guidance. While a few locations in southern Georgia/north Florida
within the Elevated area saw recent (last 48 hours) rainfall of
0.35-0.75", these areas have KBDI values of 600-700+ with ongoing
long-term severe to exceptional drought. Northwest winds gusts of
10-25 mph are already occurring with RH generally 35-50% in/near the
Elevated area. Locally elevated conditions remain likely farther
north/west into central Georgia, southeast Alabama, and the Florida
Panhandle as well.
..Nauslar.. 11/27/2025
.PREV DISCUSSION... /ISSUED 1251 AM CST Thu Nov 27 2025/
...Synopsis...
A large-scale upper-level trough positioned over the eastern CONUS
will shift east throughout the day. At the surface, a dry
post-frontal airmass will continue to overspread much of the
Southeast, accompanied by breezy northwest winds.
...Portions of Southeast Georgia and North-Central Florida...
The aforementioned dry/breezy conditions will lead to Elevated
fire-weather concerns for the region, from late morning through late
afternoon. Temperatures will warm into the upper 50s and lower 60s
F, with dew point temperatures in the low 20s F, resulting in RH
values into the low 20s and upper teens. Meanwhile, sustained winds
of 10-15 mph, gusting to 20-25 mph, will occur amid receptive fuels,
characterized by relatively high ERC values and limited recent
precipitation. Therefore, Elevated highlights have been maintained
for the region, with some expansion into the Florida Panhandle and
southern Georgia based on the latest wind/RH/fuel guidance.
...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
1240 PM CST Thu Nov 27 2025
Valid 281200Z - 291200Z
The Elevated area was expanded slightly based on the most recent
high-resolution forecast guidance. Locally elevated conditions
remain likely in portions of the Florida Panhandle, southwest
Georgia, and southeast Alabama outside of the Elevated area.
Temperatures will likely be a bit cooler tomorrow than today, but
after dry/breezy conditions today, fuels are likely to be even more
receptive.
..Nauslar.. 11/27/2025
.PREV DISCUSSION... /ISSUED 1252 AM CST Thu Nov 27 2025/
...Synopsis...
A large upper-level trough over the Eastern CONUS will move offshore
throughout the day, with enhanced zonal mid/upper level flow
persisting in its wake. At the surface, a dry/breezy post-frontal
airmass will remain in place across much of the Southeast.
...Central Florida and far Southern Georgia...
A continuation of dry northerly low-level flow into the region along
with diurnal heating will result in RH values falling into the teens
during the afternoon. Despite somewhat enhanced upper-level flow,
afternoon winds may approach 15-20 mph, at least in localized areas,
resulting in Elevated fire-weather conditions. Fuels will remain
quite receptive to large-fire spread amid a few days of persistent
dry low-level advection. The Elevated area was expanded to the
northwest based on wind/RH combos depicted in the latest
high-resolution guidance and limited recent precipitation occurring
across the region.
...Please see www.spc.noaa.gov/fire for graphic product...
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