ZCZC SPCSWOMCD ALL
ACUS11 KWNS 151921 
SPC MCD 151921 
SDZ000-NDZ000-MTZ000-WYZ000-152115-

Mesoscale Discussion 1270
NWS Storm Prediction Center Norman OK
0221 PM CDT Sat Jun 15 2024

Areas affected...northeastern Wyoming...southeastern Montana...and
into the western Dakotas

Concerning...Severe potential...Watch possible 

Valid 151921Z - 152115Z

Probability of Watch Issuance...60 percent

SUMMARY...Severe potential -- mainly in the form of damaging gusts
and large hail -- will increase with time this afternoon.  WW
issuance may be needed.

DISCUSSION...Latest visible satellite imagery shows TCU growth in
the vicinity of the Black Hills (northeastern Wyoming into
west-central South Dakota) at this time, with initial CB indicated
near the North Dakota/Montana border.  This development is occurring
on the western fringe of an instability gradient indicated across
this region, as daytime heating of an axis of 60s dewpoints has
pushed peak mixed-layer CAPE values to 2000 J/kg into the central
Dakotas.

As subtle short-wave troughing aloft -- indicated by a band of
ascent spreading across Montana and central Wyoming -- continues to
progress eastward, development of strong/locally severe storms is
expected.  With ample flow aloft contributing to sufficient shear
for organized convection, and with some potential for evaporative
enhancement of downdrafts, hail/wind potential should become
sufficient to warrant consideration of WW issuance within the next
hour or so.

..Goss/Gleason.. 06/15/2024

...Please see www.spc.noaa.gov for graphic product...

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

LAT...LON   43530285 43480368 43660424 44640492 45320513 46060480
            46640383 47630365 48080264 47830138 45640133 44150166
            43530285 

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