ACUS11 KWNS 092058
SWOMCD
SPC MCD 092058
NDZ000-SDZ000-092300-

Mesoscale Discussion 1561
NWS Storm Prediction Center Norman OK
0358 PM CDT Thu Jul 09 2026

Areas affected...portions of western South Dakota into
central/northeastern North Dakota

Concerning...Severe potential...Watch possible

Valid 092058Z - 092300Z

Probability of Watch Issuance...40 percent

SUMMARY...Isolated to widely scattered thunderstorms will bring a
risk for large hail and damaging/severe wind gusts through this
evening.

DISCUSSION...Latest observations depict ongoing thunderstorms in
close proximity to a convectively augmented shortwave trough noted
over far southern Manitoba with developing, agitated cumulus also
noted farther southwest over northwestern South Dakota. Aided by
ascent ahead of this shortwave and weak convergence along a surface
pre-frontal trough/weak wind shift, expectation is for ongoing
thunderstorm activity to persist southeastward into North Dakota and
for additional isolated to widely scattered thunderstorms to develop southwestward into western South Dakota. Moderate to strong buoyancy
(up to 2500-3000 J/kg MLCAPE noted via latest mesoanalysis) and
effective shear of 30-40 kts (as sampled by the 18z BIS observed
sounding) will support supercells and a risk for large hail
(including perhaps an isolated instance to around 2" in diameter)
and damaging/severe wind gusts. Uncertainty remains regarding
eventual thunderstorm and severe coverage, but a Severe Thunderstorm
Watch may be needed for a portion of the discussion area to cover
these threats should a corridor of greater severe potential become
evident, such as across portions of central/eastern North Dakota
where effective shear is modestly greater and where latest guidance
suggests convective coverage may be greater.

..Chalmers/Thompson.. 07/09/2026

...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fjg!-L2BZLodHv508uDWTWCL6hXV8ALmt9QUqPnQ1glolM24zIvAr7FbFmptYI78-Qb2HHpdVV6IdQLxsKIq9inj3c2C_6w$ for graphic product...

ATTN...WFO...FGF...ABR...BIS...UNR...

LAT...LON 44300060 43880080 43300099 43150108 43080123 43050180
43070271 43210331 43410363 43760396 44230404 45070381
45750329 46980165 47980060 49029970 49199950 49209808
49199769 49049754 48479753 47879764 47419786 45759966
44300060

MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN


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--- scorpsmtpd
* Origin: Capitol City Online (1:2320/107)