313
FXUS65 KGGW 070633
AFDGGW

Area Forecast Discussion
National Weather Service Glasgow MT
1233 AM MDT Mon Sep 7 2026

.KEY MESSAGES...

- Widespread rain is expected most of today as the upper low moves
  from western Montana this morning to Saskatchewan tonight.

- Strong west winds develop this afternoon and continue through
  Tuesday night.

- Cooler start and end to the week, with a brief warm up around
  mid week.




&&

.DISCUSSION...

WEATHER PATTERN OVERVIEW:
Eastern Montana will be in SW flow aloft ahead of an upper low
moving into western Montana this morning and across Central
Montana into SW Saskatchewan this afternoon. A humid airmass will
combine with the moist SW flow aloft keep an unstable atmosphere
over the forecast area which will allow for showers and
thunderstorms at times. A few storms early this morning could
become severe with large hail and damaging winds. PWAT on GGW 00z
sounding was 1.46 inches which is a record high for September.
This will provide stronger storms ample moisture for high rainfall
rates especially this morning. As the low moves into Saskatchewan
this afternoon and evening, a dry slot will move north across NE
Montana gradually diminishing the rain from south to north.
Meanwhile, the surface low will move north through NE Montana
along MT 13 this morning and into Saskatchewan this afternoon
where it will become stacked with the upper low. Strong west winds
will develop across the forecast area this afternoon and continue
tonight and Tuesday with gusts to 40 to 50 mph possible. A Lake
Wind Advisory is in effect from noon today through midnight
Tuesday night. Wrap around rain is possible at times tonight and
Tuesday over the NW half of the forecast area while the SE will be
dry most of the time.

The system exits the region Tuesday night and Wednesday and
Thursday are expected to be dry.

FORECAST CONFIDENCE & DEVIATIONS:

High confidence on rain this morning with diminishing confidence
for rain this afternoon. High confidence for strong west winds
this afternoon, tonight and Tuesday. Tweaked pops early this
morning. No other changes at this time.


&&

.AVIATION...

LAST UPDATED: 0600Z

FLIGHT CAT RANGE: VFR most of the time with areas of MVFR this
morning and tonight.

DISCUSSION:

Look for mix of low and mid clouds across the region today with
rain and scattered thunderstorms producing MVFR conditions at
times. Dry slot this afternoon and tonight will clear skies at
times. Wrap around low clouds will bring MVFR CIGS at times late
tonight and Tuesday

WINDS: East to NE 5 to 15 knots early this morning, wind will
become variable between 12z and 20z today as a surface low moves
through the area. Winds will become west 15 to 20 knots this
afternoon as the surface low moves into Saskatchewan. West winds
will be 15 to 25 knots tonight with higher gusts.


&&

.GGW WATCHES/WARNINGS/ADVISORIES...
Lake Wind Advisory from 2 PM this afternoon to midnight MDT
Tuesday night for Central and Southeast Phillips-Central and
Southern Valley-Garfield-McCone-Petroleum.

&&

$$

weather.gov/glasgow