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FXUS65 KMSO 110657
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
1257 AM MDT Mon Aug 11 2025

.DISCUSSION...

KEY MESSAGES:

- Summer like conditions through mid week

- Gusty winds and low humidity on Wednesday with increased fire
  weather concerns

- Cooler late week into the coming weekend

Very warm and mostly dry conditions will be common to start the
week. Northwest flow will bring periodic mid level moisture across
the Northern Rockies today. There will be weak afternoon
instability but enough for some virga or light showers mainly for
the terrain, especially on the Divide. Flow turns westerly on
Tuesday but overall a very similar day to Monday.

There are hints of nocturnal convection Tuesday evening in north-
central Idaho into west-central Montana early Wednesday as a weak
disturbance and elevated instability pass through. A stronger
disturbance rides along the Canadian border on Wednesday
afternoon bringing an increase in afternoon winds with gusts of
25-35 mph common. Overall, rain chances remain minimal, confined
to the Canadian border and the Divide for Wednesday. Low humidity
and gusty winds will lead to fire weather concerns across
southwest Montana and north- central Idaho.

A weak and mostly dry cold front slides in Wednesday night with
cooler and breezy conditions for Thursday and Friday. There is
considerable spread in the ensemble clusters this coming weekend
but a general idea of an upper level trough along the Pacific
Northwest Coast supports slightly below normal temperatures.
Scattered showers and thunderstorms may occur as well depending on
the depth of the trough.


&&

.AVIATION...VFR conditions are expected into Tuesday. Mid level
clouds will be common at times. There will be weak afternoon instability
but enough for some virga or light showers mostly for the
terrain, especially on the Divide. Winds will be light and terrain
driven with afternoon gusts of 15-20 kts at terminal sites.

&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...None.
ID...Heat Advisory from noon to 10 PM PDT Tuesday for Lower Hells
     Canyon/Salmon River Region...Orofino/Grangeville Region.

&&

$$