ACUS11 KWNS 270230
SWOMCD
SPC MCD 270230=20
SDZ000-NDZ000-MTZ000-WYZ000-270430-

Mesoscale Discussion 1801
NWS Storm Prediction Center Norman OK
0930 PM CDT Sat Jul 26 2025

Areas affected...Portions of the central Dakotas and far southeast
Montana

Concerning...Severe Thunderstorm Watch 546...

Valid 270230Z - 270430Z

The severe weather threat for Severe Thunderstorm Watch 546
continues.

SUMMARY...Several localized corridors of heightened severe weather
potential are emerging across the central Dakotas and far southeast
Montana.

DISCUSSION...A complex convective situation continues to unfold
across the Dakotas with several areas of localized concern beginning
to emerge. Along the ND/SD border, explosive updraft development is
noted in GOES imagery. This convection is developing within an
extremely, and thus far untapped, air mass with MLCAPE estimates of
around 4000 J/kg and mid-level lapse rates on the order of 9 C/km
(per regional 00z RAOBs). This new convection will likely develop
into one or more organized supercells given adequate deep-layer wind
shear (around 30-40 knots per regional soundings) with an attendant
threat for large to very large (1.5-2.75 inch) hail and severe
gusts. RAP mesoanalysis estimates also characterize the environment
with STP values between 3-5, and while these values are likely being
driven by extreme buoyancy, some low-level veering is noted within
the 0-2 km layer per the KABR VWP, suggesting at least some
localized tornado threat.=20

To the south, a cluster of supercells is beginning to grow upscale.
KABR velocity imagery shows an uptick in low-level outflow as this
transition occurs, suggesting severe winds may become the primary
hazard over the next hour or two.=20

Along the MT/SD border, several supercells are noted in regional
radar imagery, and storm spacing appears sufficient to maintain the
storm mode for the near-term (next hour or so). As such, the primary
hazard should remain large hail, though additional updraft
development is noted in GOES imagery across southeast MT, suggesting
that upscale growth is still probable over the next few hours as
this activity spreads northeast into the Dakotas. As this occurs,
the potential for severe winds should increase.

..Moore.. 07/27/2025

...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!6Jr0K56jbFB8Z2L7xBkArGd2nfRLvXXjECIN8NIUR4bUqJDQRctplym39_9Q8thR_norkrzg5= rruqldhBn2TMAO4ZiA$ for graphic product...

ATTN...WFO...ABR...BIS...UNR...BYZ...

LAT...LON 44860421 45000465 45240493 45590495 45850481 46000447
46620097 46679973 46539917 46209887 45779869 45419870
44929878 44639925 44529998 44740381 44860421=20

MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN


=3D =3D =3D
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