SPC MD 1887
MD 1887 CONCERNING SEVERE THUNDERSTORM WATCH 573... FOR PARTS OF CENTRAL MONTANA



Mesoscale Discussion 1887
NWS Storm Prediction Center Norman OK
0743 PM CDT Mon Aug 04 2025

Areas affected...Parts of central Montana

Concerning...Severe Thunderstorm Watch 573...

Valid 050043Z - 050215Z

The severe weather threat for Severe Thunderstorm Watch 573
continues.

SUMMARY...Thunderstorms will continue increasing in intensity and
coverage while spreading northeastward across Severe Thunderstorm
Watch 573. Severe wind gusts and isolated large hail are the main
concerns.

DISCUSSION...The latest water-vapor imagery indicates strengthening
midlevel ascent impinging on western/central MT this evening --
preceding a compact/negative-tilt midlevel trough over the northern
Rockies. Regional VWP data shows strengthening midlevel
southwesterly flow ahead of the trough, which is contributing to
around 40 kt of deep-layer shear. In response to these factors,
thunderstorms will continue increasing in intensity and coverage
while spreading/developing northeastward across central MT -- within
Severe Thunderstorm Watch 573. The strengthening large-scale ascent,
well-mixed boundary layer, and favorable deep-layer shear is
favoring the development of a loosely organized broken band of
storms, capable of producing severe outflow winds. However, the
west-southwesterly deep-layer shear vectors (orthogonal to the
developing larger-scale cold pool) are also supporting semi-discrete
supercell structures along the evolving convective band, as well as
ahead of this activity. Large hail is also a concern with these more
discrete storms.

..Weinman.. 08/05/2025

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

ATTN...WFO...BYZ...GGW...TFX...

LAT...LON   45750798 46670854 46910922 46881019 46901159 47141242
            47381260 47761249 48661120 49041032 49080936 48820820
            48310719 47580653 46260630 45670660 45660727 45750798 

MOST PROBABLE PEAK WIND GUST...65-80 MPH
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN


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https://www.spc.noaa.gov/products/md/md1887.html