657
FXUS65 KMSO 141925
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
125 PM MDT Sat Jun 14 2025

.DISCUSSION...

KEY MESSAGES:

-  Few showers/thunderstorms, mainly southwest Montana
   afternoons/evenings this weekend

-  Chance for thunderstorms will become more widespread on Monday

-  Trending toward much cooler/increased precipitation chances
   next weekend

Southwest flow continues into early next week as daytime temperatures
remain about 10 degrees above normal. A few afternoon/evening
showers and thunderstorms are anticipated this weekend, mainly
from I-90 southward, particularly focused in southwest Montana.
Considerable mid-level moisture streams overhead on Sunday
bringing a few showers but the cloud cover may act to mute most
convective potential. One exception is southwest Montana, where
models show modest instability by Sunday afternoon south of a line
from Lost Trail Pass to MacDonald Pass. This instability could
allow for a thunderstorm to briefly become strong enough for
gusty winds over 40 mph and hail.

A more significant disturbance will drive an expansion in shower/thunderstorm
coverage Monday afternoon/evening, once again focused from I-90
southward. A similar theme remains with just enough
instability/shear for the potential of a strong thunderstorm or
two across southwest Montana. Overall, moisture and precipitation
chances decrease for Tuesday as the disturbance departs.

There will be a tighter westerly gradient Wednesday and Thursday
of next week, resulting in a slight uptick in winds. It also
looks mostly dry (aside from a few afternoon thunderstorms) with
daytime temperatures holding steady, near 10 degrees above normal.
Next Friday could be a transition day with winds, slightly cooler
temperatures, and rain chances by much will depend on the timing
of an approaching trough.

Speaking of a trough, ensemble clusters are in good agreement
with a fairly deep upper level trough pressing through the
Northern Rockies next weekend (June 21-23). Temperatures are
likely to drop to below normal levels along with an increased
probability for precipitation. Much will depend on how the trough
evolves either as a closed low or an open wave, as the closed low
would allow for widespread precipitation compared to an open wave.



&&

.AVIATION...
West-southwesterly flow aloft continues today with ridgetop winds
sustaining near 15 knots through most of the day. Gusty surface
winds will develop by the afternoon with occasional gusts to 20
knots expected between 14/1900z and 15/0400z. There is less than a
30% chance for afternoon showers and thunderstorms mainly across
the elevated terrain and especially near the Continental Divide
between 14/1900z and 15/0100z with KBTM being the primary terminal
for any real chance of seeing storms.

&&

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

$$