453
FXUS65 KMSO 121959
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
159 PM MDT Fri Jul 12 2024

.DISCUSSION...Zonal (westerly) flow will remain over the Northern
Rockies as a broad ridge of high pressure encompasses the western
United States. This flow pattern will keep temperatures well above
normal for this time of year. The extreme heat and warm nights
around the Riggins area will create hazardous conditions, so a
heat advisory has been issued through Sunday evening.

Westerly winds are expected to be gusty on Saturday with widespread
gusts of 15 to 25 mph during the afternoon and evening. The
combination of winds and low afternoon humidity will create near
critical fire weather conditions.

Monsoonal moisture will be slowly creeping northward through the
weekend. Sunday and Monday have the best potential (10 to 30%)
for the development of high based showers and thunderstorms during
the afternoon and evening. Any storms that develop will be
capable of producing strong gusty erratic winds due to the
extremely dry low levels of the atmosphere.

The models are still in good agreement that the ridge of high
pressure will amplify back over the region by mid next week
keeping the persistence of hot and dry conditions. This ridge
should keep the winds relatively light and variable. Around 40% of
the models are indicating that some form of a disturbance could
knock down the ridge by next weekend.

&&

.AVIATION...VFR conditions are anticipated for the next 24 hours
at all terminals. The exception might be smoke from wildland fires
in northern Oregon drifting over KSMN and KBTM causing a reduction
in visibility.

&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...Red Flag Warning from 2 PM to 9 PM MDT Saturday for
     Deerlodge/West Beaverhead...East Beaverhead.

ID...Heat Advisory until 10 PM PDT Sunday for Lower Hells
     Canyon/Salmon River Region.

&&

$$