874
FXUS65 KMSO 070817
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
217 AM MDT Tue Oct 7 2025

.DISCUSSION...

KEY MESSAGES:

-  Widespread freeze/ frost/ valley fog today

-  Dry with seasonable temperatures through midweek

-  Unsettled weather starting Friday and lasting into next week

A ridge of high pressure will be positioned with its axis over
the Northern Rockies this morning. Clear and calm conditions with
daytime high temperatures a few degrees above normal will persist
through Wednesday. Residual low-level moisture will result in
morning fog or low stratus clouds along rivers and in some
valleys. The ridge shifts eastward on Wednesday, putting the
Northern Rockies under southwesterly flow aloft. Skies remain
clear, but the pressure gradient tightens with the upper level jet
just grazing the Idaho panhandle and northwest Montana, resulting
in an increase in south or southwesterly winds. Gusts of 20-30
mph are in the forecast for the lower Salmon River valley and the
Camas Prairie of Idaho. On Thursday, a closed low pressure
circulation becomes positioned off the coast of the Pacific
Northwest. Expect clear skies and a shift to easterly winds.

Ensemble solutions are coming into phase for unsettled weather
starting on Friday and lasting through the weekend and into next
week. The Northern Rockies will be cooler than normal, especially
for daytime highs. Precipitation returns as early as Friday,
potentially with thunderstorms for north-central Idaho and
southwest Montana. Snow levels could lower between 4000 to 5000
feet late Sunday as precipitation winds down, producing a couple
slushy inches on vegetative surfaces. If you have outdoor plans
for the weekend, please continue to check the forecast for
updates.



&&

.AVIATION... High pressure dominating the region will maintain VFR
conditions with clear skies and light winds today. Like yesterday,
the caveat will be low-level moisture creating fog and low stratus
this morning at KGPI and KMSO. Dew point depressions and overnight
low temperatures will be similar to yesterday, so keeping
fog/stratus in TAFs for this morning. Where fog and stratus forms,
the IFR/MVFR conditions will be persistent, with little
improvement expected until after 08/1700Z.

&&

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

$$