696
FXUS65 KMSO 050835
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
235 AM MDT Sun May 5 2024

.DISCUSSION...A low pressure system has moved into northern California,
the counter clockwise or cyclonic flow is pushing showers north
into Lemhi County, ID currently. Showers will continue to push
north throughout the day.

Cooler temperatures associated with this system will bring snow
levels down to about 5000 feet by Monday morning. Motorists should
expect snow over Homestake, Lost Trail, and Lolo Passes as well
as Gilmore Summit in Idaho. Chances for 2 inches of snow by Monday
morning about about 20 to 30% in higher terrain of Lemhi County,
ID.

75% of the models are showing that most locations will receive
around a quarter of an inch of rain by Wednesday. Higher end
amounts from 25% of models, demonstrate widespread 0.50 to 0.75"
of rain. Higher terrain could receive 1 to 2" of liquid
equivalent, remember above 5000 feet that could add up to 6 to 12"
or more of wet snow. Plan accordingly for any back country
activities, especially in the Clearwater, Bitterroot, Mission,
Swan, and Flathead Mountains.

Expect very breezy conditions each afternoon through Tuesday.
Initially winds will be southeasterly today, then become westerly
on Monday and Tuesday.

Once this system gets east of the Continental Divide, it will get
wound up and push moisture back west across the Divide. Cooler
and showery conditions will continue in western MT potentially
through Thursday. Higher terrain in locations like Glacier
National Park and the Bob Marshall Wilderness could receive an
additional 1 to 2 feet of snow by Thursday morning. If you have
plans in these locations please monitor future forecasts.

Thursday high pressure develops over the region with a piece of
energy from the current system breaking off, closing off, and
migrating over central California creating a blocking pattern. A
warm up and dry out is likely through at least Mothers Day.


&&

.AVIATION...Gusty east winds have developed across the region.
Throughout the morning showers will move from south to north over
Northern Rockies airspace. Heavier showers will begin to affect
visibility after 05/18z and a isolated thunderstorm will be
possible at KSMN and KBTM after 05/20z, confidence in
thunderstorms is still low. Periods of low visibility and ceilings
will be common after 06/02z as stratiform rain all terminals and
snow at KBTM develops.


&&

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

$$