885
FXUS65 KMSO 251851
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
1251 PM MDT Wed Sep 25 2024

.DISCUSSION...The main impact for late this afternoon and evening
will be the potential of localized strong wind gusts over 50 mph
associated with thunderstorms, mainly north of a line from Orofino
to Essex. Even though instability is marginal, deep-layer shear is
strong (50 kts) allowing for the potential of a strong to severe
thunderstorm or two. The higher probabilities for thunderstorms
stretch from Lookout Pass to the Flathead Valley to Glacier NP
from 6-10pm MDT. Otherwise, general gusty winds of 20-35 mph and
scattered showers will be common with and behind a cold front
this evening, especially from I-90 northward.

Behind the front, daytime temperatures will cool back to more
seasonable levels on Thursday with breezy westerly winds. The
ridge bumps back up slightly Friday and Saturday with valley
temperatures back to 10-15 degrees above normal and dry
conditions.

Nearly all the ensemble guidance have a weak trough passing
through Sunday, causing gusty westerly winds once again. At this
point the trough doesn`t dig deep enough for much precipitation,
just some light showers in Northwest Montana and along the Divide.
Daytime temperatures do cool back to seasonable levels once
again. There is also a 60-70% probability of frost in the lower
valleys of western Montana Monday and Tuesday mornings.


&&

.AVIATION...Ahead of a cold front, southwest wind gusts of 15-30
kts will be common. Mid-level moisture, deep-layer shear, and
marginal instability will allow for the potential of a strong
storm or two north of a line from Orofino to Essex. Strong winds
over 45 kts and small hail are threats with storms from around
25/2300Z to 26/0500Z. General showers will fill in behind the
front lasting into early Thursday with mountain obscurations,
especially from I-90 northward. Much of Thursday will be cooler
with breezy westerly winds continuing.



&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...Wind Advisory from 4 PM this afternoon to 11 PM MDT this evening
     for Flathead/Mission Valleys...Kootenai/Cabinet Region...
     Lower Clark Fork Region...West Glacier Region.

ID...Wind Advisory from 4 PM this afternoon to 7 PM PDT this evening
     for Northern Clearwater Mountains.

&&

$$