895
FXUS65 KGGW 302030
AFDGGW

Area Forecast Discussion
National Weather Service Glasgow MT
230 PM MDT Sat Aug 30 2025

.DISCUSSION...

KEY MESSAGES:

- Scattered showers and a few isolated thunderstorms will persist
  across eastern Montana this afternoon.

- Warm and dry conditions will finish out the holiday weekend
  before a cold front swings through the region on Tuesday.

WEATHER PATTERN OVERVIEW:
A stagnant weather pattern, evidenced by a weak rex-block low
pressure boundary will linger over the northern plains through the
weekend. Some monsoonal moisture has persisted through Montana,
but will gradually be shunted east later this evening. This
afternoon, randomly placed scattered rain showers and a few
isolated thunderstorms are everywhere but our western zones. Aside
from the normal or common summertime thunderstorms little impact
is expected, as the lack of atmospheric shear keep the hail threat
at zero. The stronger axis of instability/energy will move into
North Dakota tonight along with the moisture on Sunday, bringing
dry and warm weather for us to northeast Montana through Labor
Day.

Later in the forecast, a fairly strong closed low pressure system
will swing through central Canada on Tuesday, as it tracks toward
the Great Lakes. This will drop a cold front into Montana. A few
showers or thunderstorms are possible, mainly near the North
Dakota border with the front. Pressure rises and cold air
advection suggests wind speeds may increase, and may reach Lake
Wind criteria, but models are not indicating this yet. Current
guidance suggests slower cold air advection, which may suppress
the winds slightly. Cooler temperatures linger through midweek
while sharp western ridge slides slowly east by the weekend.

FORECAST CONFIDENCE & DEVIATIONS:

No major deviations from the NBM, aside from the first 24 to 36
hours where mostly hi-res models were favored for detailed PoPs
and winds.

Confidence in specific precipitation amounts for the region today
is low to average.


&&

.AVIATION...

UPDATE: 2027Z, Saturday afternoon, August 30

PATTERN: Upper flow is stagnant with western-states summertime
monsoon moisture in place. Just enough convective instability is
in place to set of some scattered small rain showers and isolated
thunderstorms this afternoon. Expect calmer conditions to take
over later this evening.

FLIGHT CONDITIONS: VFR, but brief MVFR is possible if a storm
happens to pass directly overhead this afternoon.

WINDS: Generally light and variable, but could be erratic and
gusty near any stronger storms.


&&

.GGW WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$

weather.gov/glasgow