894
FXUS65 KMSO 161849
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
1249 PM MDT Wed Apr 16 2025

.DISCUSSION...

KEY MESSAGES:

- Cold front to bring accumulating snow along the Continental
  Divide, especially over mountain passes above 4000 feet, this
  evening into Thursday.

- Gusty north to north east winds later today into Thursday bring
  raw backcountry conditions and choppy water on area lakes


Surface observations indicate a shift to northerly winds across
northwest Montana, accompanied by falling temperatures and
enhanced gusts. Snow has impacted travel on Highway 2 east of
Kalispell through much of the day. Showers continue to develop
both ahead of and along the advancing cold front, with some
producing lightning. The front is progressing southward and is
expected to bring a sharp temperature drop and a rapid changeover
from rain to snow, especially near the Continental Divide where
Winter Weather Advisories remain in effect.

Periods of heavier snowfallranging from 0.5 to 1 inch per
hourremain likely across southwest and west-central Montana this
evening, expanding into north-central Idaho tonight. These bursts
of snowfall may reduce visibility and create slick road
conditions, particularly during the most intense showers. While
the highest snow totals will favor the elevated terrain along the
Divide, brief slushy accumulations are possible in some valley
locations under stronger snow bands.

In addition to snowfall, gusty and shifting winds will accompany
the frontal passage. Winds will initially come from the west,
turning northerly or northeasterly behind the front. Gusts of 30
to 40 mph are expected, contributing to raw, wintry conditions in
the backcountry and likely generating choppy conditions on area
lakes. Wind Advisories remain in effect for parts of western
Montana and Lemhi County, Idaho.

Temperatures will fall sharply behind the front, with Thursdays
highs limited to the 40s to low 50s in most valleys. Snow will
linger into late Thursday morning across southwest Montana and
Lemhi County before tapering off through the day.

A brief return to high pressure is expected Friday into early
Saturday, though it appears short-lived. Most forecast models
suggest another low-pressure trough arriving by Sunday into early
next week, but exact timing and impacts remain uncertain.

&&

.AVIATION...
Satellite and surface observations highlight a cold front tracking
southward from Canada this afternoon, with the boundary tracking
across northern portions of Lake and Sanders Counties as of
16/1830Z. Widespread showers have developed along the frontal
boundary, with isolated thunderstorms being noted. The front
will reach the I-90 corridor between 16/2300-17/0100Z, with a 30%
chance for lightning and northerly winds in excess of 35kts to
impact KMSO through 17/0200Z. Higher confidence exists for
temporary visibility reductions for KGPI from 16/2000-2300Z as
northerly wind gusts of 30-35kts continue behind the front and
convective showers move through the Flathead Valley from the west.
The front will spread towards KHRF by 17/01Z, KBTM by 17/03Z and
KSMN by 17/0500z. A north-northeast wind shift is expected area
wide behind the front, with frequent gusts in excess of 20kts,
with higher gusts of 30kts or greater under convective showers
through 17/0200Z.

&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...Winter Weather Advisory until 6 PM MDT this evening for
     Kootenai/Cabinet Region.

     Winter Weather Advisory until midnight MDT tonight for West
     Glacier Region.

     Wind Advisory until 9 PM MDT this evening for Flathead/Mission
     Valleys...Missoula/Bitterroot Valleys.

     Winter Weather Advisory from 6 PM this evening to 9 AM MDT
     Thursday for Bitterroot/Sapphire Mountains...
     Butte/Blackfoot Region...Potomac/Seeley Lake Region.

ID...Wind Advisory until 6 PM MDT Thursday for Eastern Lemhi County.

&&

$$