970
FXUS65 KMSO 110827
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
227 AM MDT Tue Jun 11 2024

.DISCUSSION...

Update: No significant changes from yesterday afternoon`s
forecast. The previous discussion is below and has been updated to
reflect today`s timing.

A disturbance is still expected to move along the Canadian border
today causing breezy conditions across northwest Montana during
the afternoon and evening hours. The Mission and Flathead valleys
have a 60 to 80% probability of having wind gusts in excess of 30
mph. While the ridgetops near the Continental Divide have a 50 to
70% chance of wind gusts greater than 50 mph. These winds will
create difficult driving conditions for high profile vehicles and
tow trailers. Area lakes should anticipate choppy conditions
during the afternoon and evening hours, especially Flathead lake.

The focus of gusty winds will shift to Lemhi county and southwest
Montana on Wednesday afternoon. The I-90 corridor from Garrison
Jct to Anaconda in Montana and Hwy 28 from Salmon to Gilmore
Summit have around a 50% chance of receiving wind gusts greater
than 30 mph on Wednesday.

A transitory ridge of high pressure moves over the Northern
Rockies on Thursday causing a warming and drying period. Then the
upper level flow becomes southwesterly on Friday. This flow
pattern will keep warm temperatures over the region, but a few
showers and thunderstorms could develop over Lemhi county into
southwest Montana during the afternoon.

All the models are now indicating that a trough of low pressure
will be over the region starting this weekend and lasting into at
least the first part of next week. The discrepancies in the models
are on the timing of the cold front Saturday into Sunday and the
strength of the overall low pressure system.


&&

.AVIATION...A ridge building over the region will cause VFR
conditions today. It will be a flat ridge with nearly zonal flow
over northwest Montana today, so we expect gusty west winds in the
afternoon, which will spread south tomorrow. All the recent rain
means there`s plenty of moisture in the boundary layer that we can
expect plenty of afternoon cumulus clouds, but the strong west
winds aloft should move them out of the area quickly this evening.


&&

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

$$