880
FXUS65 KMSO 080948
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
248 AM MST Fri Nov 8 2024

.DISCUSSION...

KEY MESSAGES:

-  A ridge of high pressure will persist through Saturday,
   leading to areas of valley fog and stratus.

-  Active weather pattern returns Sunday onward, with periods of
   mountain snow through next week.

High pressure will continue to dominate the region, ensuring
stable conditions through Saturday. Valley inversions will create
favorable conditions for patchy fog and low stratus, particularly
near water sources. This is already evident in Clearwater and
Idaho Counties this morning, as seen in the GOES Nighttime
Microphysics Satellite imagery, where valley fog has developed
along the Lochsa River and Dworshak Reservoir.

A weakening Pacific trough will begin breaking down the ridge on
Sunday, allowing precipitation to spread along the Idaho-Montana
border and into northwest Montana. Snow levels will drop from
6,000-6,500 feet to 4,500-5,000 feet by Sunday morning, with
around one inch of wet snow possible across mountain passes.
Valley areas will continue to experience mild conditions, with
temperatures climbing into the 40s and 50s.

Looking ahead to next week, ensemble guidance suggests an active
weather pattern will take hold across the western U.S. and
Northern Rockies. A series of Pacific troughs embedded within a
consolidated jet stream will bring daily chances for
precipitation. This pattern is favorable for mountain snow, with
snow levels fluctuating between 4,000 and 5,000 feet as warm and
cold fronts pass through the region. There is higher confidence in
heavier snow accumulations above 5,000 feet. By Thursday, according
to the National Blend of Models (NBM), there is a 90% chance for
snow totals to exceed 6-10 inches, with most likely accumulations
in the 8-16 inch range. There is also a 10% chance for totals to
exceed 2-3 feet of snow. The westerly flow will favor snow
accumulations along the Idaho-Montana border and in northwest
Montana. /AL

&&

.AVIATION...A ridge of high pressure will remain the dominant
feature over the Northern Rockies through Saturday. Satellite
imagery this morning shows areas of valley fog and stratus across
northwest Montana and Idaho/Clearwater Counties in Idaho. This
shallow fog and stratus are expected to diminish between 16:00 and
18:00Z. Winds at area terminals will generally be light and
variable this afternoon. /AL

&&

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

$$