Text Products for AFD Issued by MSO

Area Forecast Discussion
Issued by NWS Missoula, MT
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FXUS65 KMSO 140915
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
315 AM MDT Sun Apr 14 2024

.DISCUSSION...North Central Idaho into West Central Montana are
still on track on having the best chance for showers and
thunderstorms during the afternoon and evening. These storms have
the potential of causing gusty erratic winds along with small
hail. People recreating on Flathead Lake should be aware that
there is a 50% chance for gusty south winds to 25 mph developing
between 5 and 8 pm this evening.

A low pressure system is still on track to move into the British
Columbia area on Monday causing the pressure gradient to tighten
over the Northern Rockies. This tightened gradient will create
gusty westerly winds, especially over the northwest Montana. The
mountains have a high probability of experiencing wind gusts in
excess of 30 mph. While the broad valleys of northwest Montana
have a 20 to 40 percent chance of gusts greater than 30 mph,
including Flathead lake. These winds will create choppy conditions
during the afternoon and evening on Flathead Lake.

The low pressure system over British Columbia will slide southward
over the Northern Rockies Tuesday into Wednesday causing
significantly colder temperatures. Maximum readings will drop
around 25 degrees compared from Sunday to Tuesday. This system
will also bring widespread precipitation, especially to western
Montana. The precipitation type has the potential to be snow even
down to the valley floors. Snow accumulations are anticipated to
be fairly light with minimal impacts in the valleys, but Glacier
NP and Marias Pass could receive several inches of new snow during
this event.

The models are 50/50 on the ridge building by the latter part of
the workweek, but jump up to around 80% for the ridge being over
the Northern Rockies during the weekend. This will mean a gradual
warming and drying trend in the region.


&&

.AVIATION...Showers and thunderstorms will begin to develop over
the southern Clearwater and Bitterroot Mountains between 1 and 3
pm MDT today(19z to 21z Apr 14). This activity will gradually
shift north and west with time and by early evening will generally
be found 30 miles north and south of a line from the Camas
Prairie, Idaho north and east towards west-central Montana. The
activity will wane by Sunday night. Because of the dry airmass in
the valleys, there will be more of an erratic and gusty wind
threat. The higher probability for stronger storms will be over
the terrain where small hail, lightning and moderate rainfall
could occur. Peak winds near the stronger showers could hit 35
knots. On Monday, a moderately strong westerly pressure/wind
gradient will support gusty winds...the highest probability for
greater than 25 knots will be in the mountains, along the Divide
and terminals including GPI, MSO, HRF and BTM.


&&

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

$$
National Weather Service Regional Headquarters
