885
FXUS65 KMSO 211955
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
1255 PM MST Fri Nov 21 2025

.DISCUSSION...

KEY MESSAGES:

 - Dense Fog Returns: Fog and low clouds will redevelop tonight.

 - Warm & Dry Weekend: Confidence is high for unseasonably mild
   temperatures this weekend, with highs pushing into the upper
   40s and low 50s.

-  A strong cold front will sweep through Monday, gusty winds,
   bursts of snow, and a sharp return to winter temperatures.

Fog has mostly lifted across the region with light winds and
partly to mostly cloudy skies for the rest of the day. Stable
conditions will remain through Saturday with a mix of fog and low
cloud cover returning for Saturday morning. Once the morning gray
burns off Saturday, afternoon highs will be pleasant. Valley
locations are forecast to reach the upper 40s, with some warmer
spots potentially touching 50 degrees. The forecast remains
largely dry; while some high-resolution models hint at weak
moisture spilling over the ridge into the Clearwater Mountains of
Idaho.

The ridge begins to flatten on Sunday, allowing increased high
cloud cover to stream over the region. Temperatures will remain
mild, but winds will start to increase across ridgelines late in
the day as the pressure gradient tightens ahead of the approaching
trough. A vigorous cold front is on track through the region on
Monday, bringing a significant shift in weather. The frontal
passage has been trending earlier with high temperatures on Monday
now forecast to be in the upper 30s for most valleys. Wind is the
primary widespread threat with this system, as strong westerly
flow mixes down to the surface. Gusts of 35 to 50 mph are expected
in the valleys, while exposed terrain and the Continental Divide
could see gusts exceeding 60 mph.

In addition to the wind, a burst of moderate to heavy snow is
likely at pass level during the frontal passage Monday. Lookout
Pass and Marias Pass are at the highest risk for travel impacts.
Valleys will likely see a quick shot of rain changing to snow
showers behind the front, but little if any accumulation is
currently forecast but isolated slick spots cannot be ruled out.

Behind the front, colder, more seasonable conditions take over
for the remainder of the week. The pattern looks to remain
unsettled with increasing chances for valley and mountain snow
Wednesday through Thursday.


&&

.AVIATION...Persistent mid-level cloud cover will continue to
produce mtn obscurations. Valley fog and lowered stratus are
likely to redevelop overnight tonight into Saturday morning.
Ridgetop west-northwesterly flow to 25 knots will continue with
generally calm winds anticipated at the ground of all terminal
sites west of the Continental Divide.

&&

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

$$