Winter Storm in Idaho, March 10, 2023

Area Forecast Discussion
National Weather Service Missoula MT
259 AM MST Fri Mar 10 2023

.DISCUSSION...A powerful late season winter storm is still on
track beginning this morning. Light snow is moving into our area
currently and will slowly overcome a dry surface layer for snow to
begin around daybreak. Snow levels will briefly rise during the
afternoon south of I-90, in these locations it will be possible
for a rain/ snow mix or complete change over to rain to happen.
As a strong Pacific Cold Front pushes through the region, snow
levels will once again crash to valley floors.

Along with changing snow levels, the front will be associated with
snow showers capable of brief periods of moderate to heavy snow,
strong gusty winds, and rapidly deteriorating visibility. Prepare
to slow down if driving into a wall of snow Friday afternoon or
evening.

Saturday will remain cooler than normal with afternoon snow shower
activity. Some of these showers will be capable of brief moderate
to heavy snow or graupel.

Sunday into Monday a transient ridge brings a taste of spring to
the Northern Rockies. The next weather system is continuing its
trend of a faster approach on our area but the models remain
committed to the possibility of a 50F day. Missoula yesterday had
a 38% probability of at least reaching 50, today it has increased
to 45% probability. Afternoon clouds and showers are still the
part of the forecast that could derail the high temperature
forecast.

Tuesday begins another period of active weather with temperatures
returning to normal or just slightly cooler than normal. With
chances of precipitation each afternoon through Thursday.

&&

.AVIATION...Current radar reflectivity shows precipitation
associated with an incoming warm front moving in from the
southwest. This moisture will bring snowfall initially to central
Idaho and west central Montana through Friday morning, somewhere
around and after 10/1000Z. Snow may mix with rain at times at
KHRF, KSMN, and KMSO through late morning before transitioning
back to all-snow with the cold front. Near-steady snowfall at KGPI
will be present almost all day and into the night, with blustery
winds and low visibility and ceilings expected. Snow squalls are
expected to impact KMSO, KHRF, KSMN, and KBTM after 10/1900Z,
producing winds in excess of 30 to 35 knots, visibility less than
one quarter mile, and accumulating snowfall. High impacts should
be expected through at least 11/0200Z, with lingering moderate to
heavy snowfall thereafter.

&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...     Winter Weather Advisory from 5 AM Friday to 5 AM MST Saturday
     for Kootenai/Cabinet Region.

     Winter Weather Advisory from 5 AM Friday to 11 AM MST Saturday
     for West Glacier Region.

     Winter Weather Advisory from 5 AM Friday to 5 AM MST Saturday
     for Flathead/Mission Valleys.

     Winter Weather Advisory from 5 AM Friday to 5 AM MST Saturday
     for Lower Clark Fork Region.

     Winter Weather Advisory from 5 AM Friday to 5 AM MST Saturday
     for Missoula/Bitterroot Valleys.

     Winter Weather Advisory from 5 AM Friday to 5 AM MST Saturday
     for Bitterroot/Sapphire Mountains.

     Winter Weather Advisory from noon Friday to 5 AM MST Saturday
     for Butte/Blackfoot Region.

     Winter Weather Advisory from 5 AM Friday to 5 AM MST Saturday
     for Potomac/Seeley Lake Region.

ID...Winter Weather Advisory from 4 AM Friday to 4 AM PST Saturday
     for Northern Clearwater Mountains.

     Winter Weather Advisory until 4 AM PST Saturday for Southern
     Clearwater Mountains.

     Winter Weather Advisory until 5 AM MST Saturday for Western
     Lemhi County.

     Winter Storm Warning until 5 AM MST Saturday for Eastern Lemhi
     County.

&&