FXUS65 KMSO 031836
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
1236 PM MDT Fri Apr 3 2026

.DISCUSSION...

KEY MESSAGES:

 - A strong ridge of high pressure builds in this weekend,
   bringing sunny skies and warm temperatures by Sunday.

 - The next chance for showers and cooler temperatures arrives by
   the middle of next week.

Precipitation is rapidly tapering off as drier air moves into
western Montana and north-central Idaho. High pressure begins to
build overhead on Saturday, kicking off a beautiful weekend with
clearing skies, light winds, and a noticeable warming trend.

A ridge of high pressure is building and will be firmly entrenched
over the interior Northwest on Sunday and Monday. Afternoon high
temperatures will soar 10 to 15 degrees above seasonal averages,
with many valley locations comfortably reaching into the 60s in
western Montana and the 70s in central Idaho.

As we head into Tuesday, the ridge axis will begin to shift east
ahead of our next Pacific weather maker. A broad trough in the jet
stream is forecast to move onshore and approach our area by
Wednesday. This will usher in a return to breezy winds, cooler
temperatures, and scattered rain showers that will likely persist
through Thursday. There is considerable uncertainty concerning the
evolution of the next upper-level trough. While national guidance
and medium-range models agree on a return to a cooler and more
unsettled pattern, there are notable differences regarding the
depth of the trough. If the trough digs deeper into the Great
Basin, we could see a more prolonged period of widespread valley
rain and accumulating mountain snow mid-week. If the system
remains flatter and faster, the region will experience a quicker
burst of wind and showers with lower precipitation totals.

&&

.AVIATION...A ridge building over the region is causing the
remaining moisture in the region to spread out into mid level
stratus clouds. The air mass remains moist enough that the cloud
cover is expected to persist into the evening and will act to
delay fog formation until Thursday morning. That being said, the
boundary layer remains moist and some fog is expected along area
rivers, and any clearing overnight will allow valley fog to
expand near terminals KGPI or KMSO.

&&

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

$$