533 
FXUS65 KMSO 071007
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
407 AM MDT Fri Jun 7 2019

.DISCUSSION...

Rainfall associated with a surface cold front will move east of
the Continental Divide this morning, leaving clouds and a
resurgence of rain showers and thunderstorms across the Northern 
Rockies this afternoon. Afternoon temperatures will be quite cool 
for this time of year, 10 to 20 degrees below normal for most 
locations. Gusty winds will also make a resurgence this afternoon,
with gusts in the 20 to 30 mph range common at high elevations and
across broad area valleys. Rain amounts from shower and 
thunderstorm activity today will be much less than those received 
on Thursday. High elevation valleys that experience much clearing 
tonight will cool to below freezing. Sensitive plants and gardens 
may be at risk of frost/freeze damage by Saturday morning.

The exiting trough of low pressure will transition the upper level
flow to a northwesterly trajectory on Saturday. This flow pattern
is conducive to lingering showers across much of the Northern
Rockies. The cooler airmass associated with this trough will
cause morning lows to be near freezing in high valley locations,
especially along the Continental Divide again Sunday mornings. 
Daytime temperatures will be around 15 degrees below normal on 
Saturday. A ridge of high pressure begins to build over the region
Sunday and last through at least mid next week. This ridge will 
cause a warming and drying trend over the Northern Rockies, as 
temperatures rebound to near seasonal readings by Sunday and above
normal by Tuesday. Model guidance is indicating that temperatures
will be in the mid 80s to mid 90s on Wednesday, which will be the
warmest readings so far this year. 

The ridge of high pressure begins to break down by the latter part
of the week. Meaning temperatures will cool slightly but a better
chance of showers and thunderstorms during the afternoon and
evening hours.  

&&

.AVIATION...

Rain showers and a slight chance of thunderstorms will exist
across the Northern Rockies air space today. Most terminals will
be impacted by temporarily lowered ceilings near any shower or
thunderstorm that develops. Terrain obscurations will track closely
with the shower, thunderstorm activity. Winds will gust over 20
knots over mountain passes and within broad valleys after 
07/1800Z. KGPI, KMSO, and KBTM will likely experience these wind
gusts through sunset (08/0300Z). Winds will diminish across the
region thereafter.

&&

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

$$