No watches are valid as of Thu Mar 12 20:47:02 UTC 2026.MD 0234 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF SOUTHERN NORTH DAKOTA AND NORTHERN SOUTH DAKOTA INTO EXTREME WESTERN MINNESOTA
Mesoscale Discussion 0234
NWS Storm Prediction Center Norman OK
0213 PM CDT Thu Mar 12 2026
Areas affected...portions of southern North Dakota and northern
South Dakota into extreme western Minnesota
Concerning...Severe potential...Watch unlikely
Valid 121913Z - 122115Z
Probability of Watch Issuance...5 percent
SUMMARY...Showers/thunderstorms may bring isolated strong to severe
wind gusts to portions of the Dakotas and extreme western Minnesota
this afternoon. Watch issuance is not anticipated.
DISCUSSION...Latest RAP-based mesoanalysis and forecast soundings
depict the development of very weak buoyancy across portions of the
northern Great Plains this afternoon amidst steep low-level lapse
rates. Confidence in this scenario remains low given very limited
buoyancy and low-level moisture (surface dewpoints in the mid-20s
F). Isolated lightning flashes have been noted over the past 30-60
minutes, however, indicating the development of a couple marginally
deeper cores. This shallow convection may augment very strong
northwesterly low-to-mid level flow (40-50+ kt at 1-2 km AGL per
regional VWPs), supporting the potential for isolated strong to
severe wind gusts.
..Chalmers/Gleason.. 03/12/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...MPX...FGF...FSD...ABR...BIS...UNR...
LAT...LON 46010338 46210355 46560356 46980335 47080291 47130202
47100106 46980030 46809925 46569812 46339742 45959639
45739627 45439613 45069622 44719654 44519716 44469798
44639906 44849990 45260102 45470168 45800267 46010338
MOST PROBABLE PEAK WIND GUST...65-80 MPH
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook
NWS Storm Prediction Center Norman OK
0258 PM CDT Thu Mar 12 2026
Valid 122000Z - 131200Z
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF
FAR EASTERN NORTH CAROLINA AND THE NORTHERN PLAINS...
...SUMMARY...
An isolated threat for damaging winds will continue for another hour
or so across far eastern North Carolina. Strong convective wind
gusts remain possible across the northern Plains this afternoon as
well.
...20Z Update...
Probabilities have been removed behind a line of thunderstorms
across eastern North Carolina. A short-term severe threat persists
across the Outer Banks, where isolated damaging winds may occur for
the next hour or so. Otherwise, thunderstorm probabilities have been
trimmed from eastern MT, with no changes to the Marginal Risk across
the northern Plains.
..Broyles.. 03/12/2026
.PREV DISCUSSION... /ISSUED 1044 AM CDT Thu Mar 12 2026/
...Carolinas and North Florida...
A broken line of low-topped thunderstorms will continue to move
quickly northeastward this afternoon across parts of the Carolinas
in tandem with a mid-level shortwave trough across the Southeast.
Strong low to mid-level southwesterly flow should promote some
threat for occasional severe/damaging winds with this line as
filtered daytime heating fosters modest steepening of low-level
lapse rates and weak destabilization. Even so, poor mid-level lapse
rates will tend to limit the development of any more than modest
instability overall. While low-level winds have generally veered to
southwesterly per recent VWPs from LTX/MHX, there is still
sufficient speed shear in the 0-1 km layer to support embedded
circulations within the line, and perhaps a brief tornado or two.
The Slight Risk has been adjusted for latest observational and
guidance trends to reflect the mainly damaging wind threat with the
line this afternoon, before it moves offshore into the western
Atlantic. A small Marginal Risk area has also been maintained for
parts of north FL where an isolated damaging wind threat should
exist in the short term with the far southern portion of the line.
...Northern Plains...
Very strong mid-level winds (around 100-120 kt at 500 mb) will
spread southeastward across the northern Plains this afternoon in
tandem with a low-amplitude mid-level shortwave trough moving over
the northern Plains. Latest NAM/RAP forecast soundings suggest very
weak instability may develop south of a front across the northern
Plains, such that shallow convection may develop with some threat of
lightning. This convection could augment the already strong
west-northwesterly low/mid-level flow, resulting in strong surface
wind gusts. Isolated significant wind gusts (65+ kt) could occur
with any sustained convection that develops, but confidence in this
scenario remains low.
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook
NWS Storm Prediction Center Norman OK
1222 PM CDT Thu Mar 12 2026
Valid 131200Z - 141200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Severe thunderstorms are not expected on Friday.
...Synopsis...
A cold front currently pushing east towards the southeastern U.S.
coast will continue to migrate offshore and southward along the FL
peninsula through Friday morning. This boundary will eventually
stall across south FL before gradually lifting north as a very
diffuse warm frontal zone. Diurnal heating of a moist and largely
uncapped environment will support thunderstorm development by early
to mid-afternoon - especially along the southwestern FL coastline
where sea-breeze interactions will locally augment ascent. Very weak
flow through 6 km will limit the potential for organized severe
thunderstorms, though the thermodynamic profiles may support very
isolated strong downburst winds.
Further north, an intense cyclone will traverse the lower Great
Lakes into the Northeast through the day. Cold mid-level
temperatures may support adequate instability for sporadic lightning
flashes along the NY/PA border. Strong (40-50 knot winds) just above
the surface may be mechanically mixed to the surface by any shallow
convection that can develop, as hinted by recent HRRR solutions.
However, morning guidance depicts considerable spread regarding CAPE
availability that limits confidence in the overall lightning (or
severe wind) potential.
..Moore.. 03/12/2026
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook
NWS Storm Prediction Center Norman OK
0214 PM CDT Thu Mar 12 2026
Valid 141200Z - 151200Z
...NO SEVERE THUNDERSTORM AREAS FORECAST...
...SUMMARY...
Severe thunderstorms are not expected on Saturday.
...Synopsis...
Zonal upper-level flow over the CONUS early Saturday will give way
to amplification of an upper trough late Saturday and into Sunday
over the Plains. Rapid cyclogenesis is anticipated as a surface low
deepens within the left-exit region of an intense upper jet and
migrates from eastern WY into the eastern Plains. Increasing
southerly winds will advect moisture northward into the southern
Plains through the forecast period, but in the wake of the recent
frontal passage, moisture return will likely be insufficient to
overcome stout capping at the base of an expansive EML. Sporadic
lightning flashes appear possible within the warm advection branch
of the intensifying cyclone, but forecast soundings show poor
agreement with regards to the availability of MUCAPE. Thunderstorms
are most probable across south Florida and along the eastern FL, GA,
and SC coasts. While displaced from the strengthening low over the
Plains, southerly winds will support a weak warm advection regime
within a moist, buoyant, and uncapped environment. Diffuse forcing
for ascent and poor flow aloft should limit the potential for severe
thunderstorms.
..Moore.. 03/12/2026
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