ZCZC SPCSWOMCD ALL
ACUS11 KWNS 050855 
SPC MCD 050855 
SDZ000-NDZ000-MTZ000-051000-

Mesoscale Discussion 1374
NWS Storm Prediction Center Norman OK
0355 AM CDT Tue Jul 05 2022

Areas affected...portions of southeastern Montana and vicinity

Concerning...Severe Thunderstorm Watch 433...

Valid 050855Z - 051000Z

The severe weather threat for Severe Thunderstorm Watch 433
continues.

SUMMARY...Severe risk continues over roughly the southern half of WW
433, as well as areas to the south.  A new WW may be required, given
the scheduled 05/10Z expiration of WW 433.

DISCUSSION...Latest radar loop shows scattered strong/isolated
severe storms ongoing at this time over portions of the southeastern
quarter of Montana -- i.e. within the southern half of WW 433 and
areas to the south of the watch.

The storms are ongoing in an area of QG-forced ascent -- owing to an
upper low over southeastern British Columbia, and a
southeasterly/easterly low-level jet over the northern High Plains. 
While the airmass across east-central and northeastern Montana and
into most of western North Dakota remains relatively stable, an axis
of 500 to 1500 J/kg mixed-layer CAPE persists from southeastern
Montana east-southeastward to South Dakota.  This axis is oriented
along, and just north of, a surface front extending from
northeastern Wyoming south-southeastward across Nebraska.

Isolated storms capable of producing severe-level wind gusts and/or
hail are expected to persist over the next several hours, given the
previously described dynamic/thermodynamic/kinematic environment. 
As such, a new WW may be needed, given upcoming/scheduled expiration
of WW 433.  Such a watch would likely include counties currently in
the southern half of WW 433, and areas to the south/southeast from
southern Montana to northwestern South Dakota and far southwestern
North Dakota.

..Goss.. 07/05/2022

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

ATTN...WFO...BIS...UNR...BYZ...GGW...

LAT...LON   45790829 46530827 46980765 46990679 46540434 45730335
            45340255 44910345 45410503 45480629 45610775 45790829 

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