Expires:No;;732481
FXUS65 KMSO 032000
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
100 PM MST Sat Jan 3 2026

.DISCUSSION...

KEY MESSAGES:

 - Slippery Travel: Patchy freezing rain and black ice may cause 
   slick travel tonight.

 - Gusty Winds: Wind gusts up to 60 mph are expected on the Camas
   Prairie near Grangeville, Idaho, tonight into Sunday morning.

 - Active Winter Pattern: A series of storms will bring frequent 
   mountain snow and a mix of rain and snow to the valleys through
   the middle of the week.

A dip in the jet stream will keep the weather active and 
unsettled over the next several days, bringing multiple rounds of 
precipitation. While mountains will see snowfall, valley residents
should continue to prepare for a messy mix of rain and freezing 
rain as warmer air tries to push out the cooler air currently 
trapped in many of our valleys.

The primary concern for the rest of today and tonight is the 
potential for patchy freezing rain. Cold air is currently trapped 
in many western Montana valleys, and as moisture moves in aloft, 
it will fall into this near-freezing air. Warming has been 
sluggish in the northern Bitterroot, Missoula, Mission, and 
Flathead Valleys, where early afternoon temperatures have hovered 
in the low to mid-30s.

Since temperatures are forecast to remain fairly steady 
overnight, these valleys will be right at the freezing mark as 
showers pass through this evening. This setup is a prime candidate
for patchy freezing rain. If you are traveling, be aware that 
roads may look wet but could actually be icy; "black ice" is a 
threat on bridges, overpasses, and side streets.

In north-central Idaho, the focus shifts to gusty winds. A 
localized weather pattern will likely produce gusts around 50 mph 
along Highway 95 from Riggins to Grangeville, and 50-60 mph across
the Camas Prairie and near Grangeville tonight. These winds 
should peak between 5:00 AM and 10:00 AM Sunday morning before 
tapering off.

The active pattern continues through Wednesday as several weather
disturbances move through the region.

Monday & Tuesday: Expect periods of rain and snow for the valleys
and steady snow for the mountain passes.

Wednesday: This looks to be the windiest day for the entire 
region, with gusts of 20-30 mph likely for most locations as a 
stronger front pushes through. Snow levels will generally hover 
near valley floors through Tuesday before dropping to most valley 
floors with the front on Wednesday. The heaviest snow 
accumulations through mid-week will be along the Idaho/Montana 
border, where 5 to 12 inches of snow are possible in the 
mountains.

Late Week: While there is high confidence in the active weather 
through Thursday, models are split (about 50/50) on what happens 
Friday and Saturday. One scenario keeps the "dip" in the jet 
stream over us (meaning more snow), while the other builds a 
"ridge" (meaning dry but foggy and stagnant air).


&&

.AVIATION...Valley inversions and light winds remain common from
the northern Bitterroot Valley through northwest Montana, where
fog and low clouds remain. KGPI and KMSO remain the primary sites
impacted by persistent low clouds and fog. Visibility and ceiling
improvement is still expected this afternoon, but fog is likely to
return this evening. A weather disturbance will bring a wintry mix
to the stable valleys later this evening, generally after
04/0300Z, which will bring lower ceilings and visibility through
the night. Snow showers are expected in the mountains across the
region tonight into Sunday.

&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...None.
ID...Wind Advisory from 9 PM this evening to noon PST Sunday for 
     Lower Hells Canyon/Salmon River Region...
     Orofino/Grangeville Region.

&&

$$