ACUS11 KWNS 230629
SWOMCD
SPC MCD 230629=20
NDZ000-MTZ000-230830-

Mesoscale Discussion 2026
NWS Storm Prediction Center Norman OK
0129 AM CDT Wed Aug 23 2023

Areas affected...far east-central Montana and into west/central and northwestern North Dakota

Concerning...Severe potential...Watch unlikely=20

Valid 230629Z - 230830Z

Probability of Watch Issuance...5 percent

SUMMARY...Local/isolated severe potential may persist another 1 to 2
hours, before diminishing. WW issuance is expected to remain
unnecessary due to limited areal and temporal nature of the threat.

DISCUSSION...Latest radar loop shows a cluster of strong storms
moving quickly northeastward in the vicinity of the east-central Montana/west-central North Dakota border area at this time. A
report of a 60 MPH wind gust was received roughly an hour ago from
Dawson County Montana, and WDSS data has show occasional indications
of hail around .75" in diameter.

Based on output from multiple CAMs, this convection should weaken
markedly over the next 1 to 2 hours, with any severe risk likewise
diminishing. With that said, the convection is more vigorous, and
more widespread, than CAM output would suggest, which calls this
conclusion into question a bit. Further, with an axis of 1000 to
1500 J/kg mixed-layer CAPE present per RAP-based objective analysis
across west-central and northwestern North Dakota, such rapid demise
of convection as suggested by the CAMs may be just a bit aggressive.

With that said, a cooling/neutral to slightly stable boundary layer
with northeastward extent across northwestern North Dakota appears
likely to limit stronger wind-gust potential to roughly the next
hour or so as storms move through the axis of greatest low-level moisture/instability. This, combined with a lack of any updrafts
intense enough to produce hail in excess of 1" in diameter thus far
despite convection moving through the most favorable thermodynamic
environment at this time, suggests that severe potential will remain
limited, and likely to last no more than another 1 to 2 hours.

..Goss/Guyer.. 08/23/2023

...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!7rzwMJBsee-JLI8WUfFAYva5VpJMa2H58tdN5Odac4LAVSP_oae-49uRw814dTfvXsqSmf-hI= P5AyiUQQmdcoL7saIc$ for graphic product...

ATTN...WFO...BIS...GGW...

LAT...LON 46770425 47330476 48150496 48520396 48470294 47740231
47000230 46900278 46770425=20


=3D =3D =3D
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