110
FXUS65 KMSO 011740
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
1140 AM MDT Sun Jun 1 2025

.DISCUSSION...

KEY MESSAGES:

-  25 percent chance for lightning in the mountains of Lemhi
   County and Silver Bow County later today

-  Cooler and wet in the backcountry along the Divide Monday, with
   a 40 percent chance for 1 inch of snow in Glacier National Park
   (Lewis Range)

-  80-90% chance of frost Tuesday morning across high valleys, 20%
   chance in the lower Montana valleys above 2500 feet.

-  Moderating temperatures with showers(mainly towards the Divide)
   possible each day this week.


A few strong thunderstorms remain possible this afternoon and
evening, primarily from Lemhi County eastward into southwest
Montana. The main hazards will be gusty outflow winds exceeding 50
mph and hail. Those with outdoor plans should secure loose items
and remain weather-aware. As always, when thunder roars, go
indoors.

On Monday, an upper-level trough will move across the Northern
Rockies, bringing increased precipitation chances-especially along
and east of the Divide. Conditions will be notably cooler, with
Glacier National Park potentially seeing a dusting of snow above
6000 feet. Anyone recreating in the high terrain should be
prepared with rain gear and warm clothing. Monday is shaping up to
be the coolest day of the week.

By Tuesday morning, model guidance (MOS) suggests low
temperatures dipping into the 30s across parts of the region. This
could result in patchy frost, particularly in colder valley
locations. Sensitive vegetation may need protection. A similar
setup may allow for additional frost potential Wednesday morning
in high valley areas.

For the remainder of the workweek, precipitation chances look
limited, with only isolated convective showers each day, mainly
confined to the Divide and points east.

Looking ahead to next weekend, forecast confidence decreases.
Ensemble cluster analysis shows about 30% of members support a
digging trough over Montana, while the remaining 70% favor milder,
drier conditions. While deterministic runs of the ECMWF and
Canadian models reflect the trough scenario, it remains a lower
probability solution based on the broader ensemble spread.


&&

.AVIATION...Breezy north to west winds are expected today
especially from north-central Idaho and points east. A few showers
are possible from Lemhi County into southwest Montana. There could
be a few thunderstorms as well, but they may only be confined to
the terrain around KBTM. Storms forming around KBTM will have the
potentially for erratic outflow winds gusting 35 to 45 mph. An
upper level trough will bring showers along the Divide tonight
into Monday. Light snow in Glacier National Park above 6000 feet
MSL will bring lower ceilings and mountain obscurations.


&&

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

$$