834
ACUS11 KWNS 010110
SWOMCD
SPC MCD 010109
WYZ000-MTZ000-010315-

Mesoscale Discussion 1859
NWS Storm Prediction Center Norman OK
0809 PM CDT Thu Jul 31 2025

Areas affected...Portions of central/northern Wyoming into far
southeastern Montana

Concerning...Severe potential...Watch unlikely

Valid 010109Z - 010315Z

Probability of Watch Issuance...20 percent

SUMMARY...Thunderstorms should increase in coverage over the next
few hours. Severe wind gusts and isolated large hail may accompany
the stronger storms.

DISCUSSION...Widely scattered thunderstorms are developing within a
plume of steep deep-layer lapse rates in central WY (per RIW 00Z
sounding), with additional convective development evident along
differential heating zones/outflow boundaries and over the higher
terrain in northern WY. This uptick in convection may be aided by a
subtle/embedded midlevel impulse moving into the area. Over the next
few hours, these storms will continue tracking/developing
northeastward into an environment characterized by weak-moderate
surface-based buoyancy and around 30-40 kt of effective shear. This
should promote a few loosely organized cells and clusters, capable
of producing severe wind gusts and isolated large hail. Current
indications are that the severe risk will remain too brief/isolated
for a watch, though convective trends are being monitored.

..Weinman/Thompson.. 08/01/2025

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

ATTN...WFO...UNR...CYS...BYZ...RIW...

LAT...LON   44290496 43810521 43250579 43000709 43240809 43780852
            44250846 45160786 45540704 45590627 45310544 44930502
            44290496

MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN