No watches are valid as of Thu Dec 18 19:38:01 UTC 2025.MD 2259 CONCERNING BLIZZARD FOR THE EASTERN DAKOTAS INTO WEST AND NORTHWEST MINNESOTA
Mesoscale Discussion 2259
NWS Storm Prediction Center Norman OK
0909 AM CST Thu Dec 18 2025
Areas affected...The Eastern Dakotas into west and northwest
Minnesota
Concerning...Blizzard
Valid 181509Z - 182015Z
SUMMARY...Blizzard conditions are expected to continue across parts
of the eastern Dakotas and into parts of west/northwest MN through
early/mid afternoon.
DISCUSSION...Latest surface observations and web cams from southeast
SD northward through the Red River Valley of the north show
widespread visibility reductions to 1/4 mile or less with some areas
experiencing white out conditions - especially across northeast ND
into northwest MN where moderate to heavy snowfall rates are
contributing to the visibility reductions under a developing snow
band. Heading through the afternoon, the strongest push of low-level
cold advection should migrate from the eastern Dakotas into southern
MN/northern IA. Although the heaviest snowfall will likely shift
eastward into northern MN through the day, light snow and persistent
strong northerly winds will continue to support blizzard conditions
through the Red River Valley through at least mid-afternoon and
possibly until around 00z. Further south/southeast, the antecedent
snow pack is not as widespread compared to locations further north,
but a combination of light to moderate snowfall and intense surface
winds (gusting between 40-50 mph) will likely contribute to areas of
blizzard conditions into west/southwest MN.
..Moore.. 12/18/2025
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...MPX...FGF...FSD...ABR...BIS...
LAT...LON 45379439 44949441 44709454 44459491 44249551 44169600
44199677 44309723 44579749 45039785 45599814 45949836
46839890 48129916 48699904 48959878 49069819 49059675
49029527 48549520 47799538 47109550 46189521 45379439
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
1031 AM CST Thu Dec 18 2025
Valid 181630Z - 191200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
THE MISSISSIPPI/TENNESSEE/LOWER OHIO VALLEYS...AND PORTIONS OF
COASTAL NORTH CAROLINA...
...SUMMARY...
Isolated strong to severe thunderstorms capable of producing
occasional damaging winds and perhaps a tornado or two may occur
through this evening across parts of the lower/mid Mississippi
Valley into the Tennessee Valley/Southeast, and late tonight across
portions of coastal North Carolina.
...Tennessee Valley/Lower Ohio Valley into the Southeast...
A pronounced mid/upper-level shortwave trough with attendant 70-90
kt mid-level jet will advance quickly eastward today across the
Upper Midwest into the MS/OH/TN Valleys. An associated deep surface
low over northern MN this morning is forecast to continue developing
northeastward into Ontario/Quebec through tonight, with a trailing
cold front forecast to sweep east-southeastward over much of the
mid/lower MS Valley into the OH/TN Valleys and Southeast. Low-level
moisture return ahead of the cold front remains quite limited,
except for parts of MS/AL where low to mid 60s surface dewpoints are
beginning to spread inland. Even so, wind fields remain quite
favorable for thunderstorm organization, with ample low-level and
deep-layer shear present. Current expectations are for a low-topped
line of convection to further develop along the cold front through
this afternoon/evening. Although instability is expected to remain
minimal with northward extent into the OH/TN Valleys, there is still
potential for strong to severe gusts that will be convectively
enhanced beyond the already strong background gradient wind field.
Some chance for a tornado may also exist across parts of MS/AL where
greater instability/low-level moisture will reside. Given latest
observational and guidance trends, a Marginal Risk has been included
where the best potential for occasional strong to damaging winds is
apparent.
...Coastal North Carolina...
Isolated strong to locally severe convection may occur late tonight
through early Friday morning as an increasingly negative-tilt
mid-level trough and a related robust strengthening of the
deep-layer wind field approach eastern NC. The gradual modification
and erosion of continental/cold air is a key uncertainty due to
persistent surface high pressure along the East Coast into western
Atlantic. Some guidance such as the 12Z NAM may be a bit too
aggressive regarding late-night near-surface-based destabilization.
Still, the main area of concern is for the immediate NC coastal
areas/Outer Banks, where somewhat greater airmass
modification/low-level moistening should occur amid strong low-level
and deep-layer shear. If surface-based thunderstorms can form and
spread northeastward across this area, they could pose a threat for
isolated severe/damaging winds and perhaps a tornado. But, it is
also possible that convectively enhanced wind gusts materialize
inland (including Piedmont areas) in the predawn hours, although
confidence in this occurring remains low.
..Gleason/Weinman.. 12/18/2025
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1114 AM CST Thu Dec 18 2025
Valid 191200Z - 201200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Thunderstorms may occur over the Mid Atlantic and Northeast early
Friday, and in the Pacific Northwest Friday afternoon through Friday
night. Severe storms are not forecast.
...Synopsis and Discussion...
A large negative-tilt upper trough will extend from the upper Great
Lakes into the Southeast Friday morning, and will eject
northeastward across Mid Atlantic and New England late in the day.
At the surface, low pressure will move across southern Quebec, with
a cold front extending south from NY into the eastern Carolinas
Friday morning. This front will quickly push into New England by
midday and will already be off the NC Coast. Southerly surface winds
will bring 50s F dewpoints as far north as NJ ahead of the front,
with low 60s F into eastern NC and VA.
...Northeast...Eastern VA and NC...
Strong lift along the cold front will likely support a higher
reflectivity line of precipitation and possibly shallow convection
from eastern PA into MD and eastern VA/NC Friday morning, which will
rapidly move east toward the Hudson Valley and extending southward
and offshore between 15-18Z. Forecast soundings indicate a cool
boundary layer and zero SBCAPE over northern parts of the frontal
zone, with minimal SBCAPE farther south. There may be a short window
of convectively augmented wind gusts prior to the line moving
offshore, but instability, early time of day and limited lapse rates
aloft suggest minimal overall risk.
..Jewell.. 12/18/2025
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0112 PM CST Thu Dec 18 2025
Valid 201200Z - 211200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Isolated thunderstorms are possible across western Oregon and
northern California late Saturday night.
...Synopsis...
A broad cyclonic flow regime aloft will develop from the central
into the eastern CONUS on Saturday, with an upper trough amplifying
from the northern Plains into the Great Lakes. Gradual height rises
will occur over the West, with weak flow aloft across the southern
tier of states. Late in the period into Sunday morning, height falls
will begin across the Pacific Northwest with an approaching wave.
At the surface, high pressure will exist along the East Coast with
southerly winds across the western Gulf and into the southern
Plains. While some degree of low-level moisture return will occur,
another cold front will push south across the Plains behind the
developing Great Lakes system. As a result, any instability over
coastal TX/LA should remain capped.
Chances for thunderstorms will develop late in the period across the
Pacific Northwest as a plume of midlevel moisture arrives out of the
west. This moistening and warming in the 850-700 mb layer will
result in weak elevated instability sufficient for isolated
lightning.
..Jewell.. 12/18/2025
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