863 
FXUS65 KMSO 202007
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
207 PM MDT Fri May 20 2022

.DISCUSSION...The atmosphere remains unstable after last night's
second front passage, allowing for numerous showers to develop
across the region. Also a very subtle feature is enhancing the
instability over northern Idaho and northwest Montana. This
enhancement is causing an increase in coverage with a few embedded
thunderstorms. These storms will be capable of producing graupel
to small hail. The convection will diminish during the evening
hours. 

The lingering cold air along with cloud cover breaking up
throughout the night, temperatures should drop to dramatically.
The high valleys of north central Idaho along with the valleys
across western Montana will experience minimum temperatures near
freezing. The valleys along the Continental Divide are anticipated
to have temperatures drop into the mid 20s by Saturday morning.

Temperatures will warm during the day as the atmosphere steadily
becomes unstable. Afternoon showers and potential thunderstorms
are anticipated to develop across north central Idaho into
southwest Montana. Once again the convection will diminish during
the evening. 

Sunday appears to be much of the same as temperatures warm a few
degrees warmer compared to Saturday. A weak disturbance will keep
off the shower and thunderstorm potential during the afternoon,
this time the greatest threat will be over Lemhi county into
southwest Montana. 

Monday and Tuesday will be similar as temperatures hover just
below seasonal readings with afternoon/evening convection. The 
models continue to trend towards a ridge of high pressure moving 
over the Northern Rockies by mid week. This ridge will cause a dry
period and temperatures potentially climbing to around 10 degrees
above normal. 


&&

.AVIATION...Widespread showers will continue to develop and stream
over the Northern Rockies this afternoon and evening. Showers will
diminish around sunset. Expect brief moderate to heavy
precipitation with these showers, along with up to pea size hail
in isolated areas. Breezy north winds with gusts up to around
20kts will be possible in and around the showers.





&&

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

$$