239
FXUS65 KMSO 140816
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
216 AM MDT Sat Jun 14 2025

.DISCUSSION...

KEY MESSAGES:

-  Thunderstorms for southwest Montana this afternoon/evening

-  Afternoon thunderstorm theme will continue for southwest
   Montana on Sunday

- Chances for thunderstorms will become more widespread on Monday


A rather stubborn low pressure circulation, quite prominent on
satellite water vapor imagery this morning, will remain quasi-
stationary off the coast of British Columbia. Ensemble guidance is
in good agreement to keep it in place into early next week. The
implication will be a broad trough axis over the West Coast
resulting in southwesterly flow aloft over the Northern Rockies.
Some Pacific moisture will keep showers and thunderstorms in the
forecast for southwest Montana today and on Sunday. Forcing for
ascent will be harder to come by elsewhere until Monday, when a
shortwave disturbance will help chances for evening showers and
thunderstorms spread into north-central Idaho, west-central
Montana, and along the Continental Divide. Temperatures will be
about 10 degrees above normal.

Broad high pressure will take over by midweek as the Pacific low
moves south and deepens the trough over the West Coast. Ensemble
guidance is in favor of the Pacific low moving into the Pacific
Northwest by the end of the week. About 40% of solutions keep a
closed circulation in tact, while the remainder show an open wave.
The former will result in a more widespread precipitation event,
while the latter will favor a much milder outcome as far as
precipitation goes. Similar systems have had a habit of showing
up as open waves in recent history.


&&

.AVIATION...Southwesterly flow aloft with the upper level jet
positioned over northwest Montana today will result in chances for
thunderstorms over southwest Montana and gusty west or southwest
winds across the Northern Rockies. There will be about a 30%
chance for thunderstorms at KBTM this afternoon starting around
14/2000Z through this evening.


&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...None.
ID...None.
&&

$$