ACUS11 KWNS 272049
SWOMCD
SPC MCD 272049
MTZ000-IDZ000-272245-

Mesoscale Discussion 2152
NWS Storm Prediction Center Norman OK
0349 PM CDT Thu Aug 27 2026

Areas affected...portions of western and central Montana

Concerning...Severe potential...Watch possible

Valid 272049Z - 272245Z

Probability of Watch Issuance...60 percent

SUMMARY...Thunderstorm coverage to increase through the afternoon,
with potential for damaging wind. A watch will be possible.

DISCUSSION...Forcing for ascent is overspreading portions of Idaho
into western Montana from an upstream trough across the Pacific
Northwest. This will likely lead to an increase in thunderstorm
development across western Montana this afternoon. Initially,
thunderstorms will form near the high terrain before spreading
eastward through the lower valleys late afternoon/evening.

Though cirrus has been present, filtered daytime heating across the
lower terrain has yielded temperatures in the 90s F. Surface dew
points are generally in the mid-40s to 50s, with mainly mid-level
moisture contributing to thunderstorm development. While moisture is
modest, surface heating has allowed for steepening mid-level lapse
rates and marginal instability (with MLCAPE around 500 J/kg). Large
dew point depressions and steep low-level lapse rates will likely
result in outflow dominate storms with the primary threat of
damaging wind. Guidance suggests that one or more clusters may
emerge and spread north and east through the evening, which may
produce more focused corridors of severe gusts around 60-75+ mph. A
watch will be possible this evening to cover this potential.

..Thornton/Mosier.. 08/27/2026

...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fjg!_Tu-_2wp2TAqu3jyqc9WqBudIjKVL8Xy6TbwZR5y1smC9C-rgp4w_Ek_EBx0yHAK-wOywVyuaR3-M-RTakdg2nwRfsg$ for graphic product...

ATTN...WFO...BYZ...TFX...MSO...

LAT...LON 47251331 47901334 48421292 48721252 48811182 48701095
48491036 48000997 47240967 46360980 45851024 45501097
45351223 45371337 45441370 45491380 47251331

MOST PROBABLE PEAK WIND GUST...65-80 MPH


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--- scorpsmtpd
* Origin: capitolcityonline.net * KY, USA (1:2320/107)