FXUS65 KMSO 021817
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
1217 PM MDT Sat May 2 2026

.DISCUSSION...

KEY MESSAGES:

-  Warm and dry for most areas through the weekend.

-  An exception: Scattered slow-moving showers and isolated
   thunderstorms this afternoon for northwest Montana, shifting
   southward Sunday.

-  Northeast breezes increase along with cooler temperatures early
   next week.

The regional weather pattern transitions from ridging to
northwesterly flow this afternoon and evening. The Northern
Rockies will remain positioned between a persistent low over the
Hudson Bay and an upper- level low currently off the California
coast into early next week.

This Afternoon-Sunday: Warm and mostly dry conditions will
persist through Sunday, with daytime temperatures averaging 10-15
degrees above normal (though remaining below record levels). The
primary exception to the dry trend will be increased mid-level
moisture and weak forcing/instability across northwest Montana
this afternoon and evening, leading to scattered showers and
isolated thunderstorms. This moisture shifts southward on Sunday,
bringing a similar threat to southern Idaho County eastward into
Southwest Montana during the afternoon.

Impact Potential: Stronger showers or isolated storms may produce
sudden, gusty outflow winds of 30-40 mph.

Monday and Tuesday: A backdoor cold front will push across the
Continental Divide Monday morning, bringing northeasterly gusts of
20-30 mph to western Montana. This enhanced northerly gradient
will persist into Tuesday, with gusty winds reaching into north-
central Idaho during the afternoon hours as well.

Impact Potential: Expect choppy conditions on area lakes at
times.

Temperatures will briefly return to seasonal levels, with highs
in the 60s for most lower elevations of western Montana, 70s in
north-central Idaho. While a few showers and thunderstorms remain
possible Monday and Tuesday, overall rainfall totals will be
light.

Wednesday and Beyond: Ensemble clusters show nearly 100%
agreement that a ridge will re-establish along the West Coast
during the latter half of next week. While uncertainty remains
regarding the exact amplitude and position of the ridge, the
overall trend favors a warmup back into the 70s for most valley
locations, low 80s in north-central Idaho. If the ridge centers
further west, the Northern Rockies would remain in a northwesterly
flow, keeping daily shower chances in the forecast; however,
widespread or significant precipitation appears unlikely.

&&

.AVIATION...High and mid-level cloud cover will continue to stream
across the region through the weekend. Winds will remain light
and terrain- driven, with typical afternoon gusts of 10-15 kts at
most terminals.

Weak instability this afternoon will be sufficient to trigger
scattered showers and isolated thunderstorms across northwest
Montana (including KGPI) and along the Continental Divide. High-
resolution guidance also suggests a low-end potential for
vicinity showers at KMSO. Stronger showers or storms may produce
erratic outflow gusts near 30 kts.

On Sunday, the mid-level moisture axis shifts south, focusing
convective potential (showers/TS) from southern Idaho County
eastward into Southwest Montana. VFR conditions will generally
prevail outside of direct convective impacts.

&&

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

$$