191
FXUS65 KGGW 290820
AFDGGW

Area Forecast Discussion
National Weather Service Glasgow MT
220 AM MDT Fri Aug 29 2025

.DISCUSSION...

KEY MESSAGES:

- Monsoonal moisture will be over NE Montana in varying degrees
  through Saturday afternoon. Isolated showers and thunderstorms
  are expected over parts of the area during that time.

- Warm, summer like temperatures will prevail this weekend.

- Cold front moves in either Monday night or Tuesday, bringing
  north winds and the chance for some showers and thunderstorms.

WEATHER PATTERN OVERVIEW:

A weak upper flow aloft within an upper trough will keep varying
degrees of monsoonal moisture over NE Montana today, tonight and
Saturday. The overall moisture will be deeper over central and
southern Montana which will limit most of the precipitation
chances to SW of a line near Opheim, Glasgow, Circle and Glendive.
Most of the moisture that makes it into NE Montana will be at the
mid and high levels which will result in mainly cloudy skies
through Saturday. At this point, there is a 30-50 percent
probability of Phillips, Petroleum, and western Garfield Counties
receiving at least a tenth of an inch of rain from this system
while areas east of Glasgow, Circle and Glendive have less than a
20 percent chance of seeing any measurable precipitation at all.

The system moves to the east Saturday night and Sunday and Labor
Day will be warm and dry with highs in the 80s to near 90.

A cold front is expected either Monday night or Tuesday that will
bring isolated showers and thunderstorms. There is low confidence
on precipitation amounts and location with this front. Cooler
temperatures will prevail Tuesday and Wednesday.

The remainder of the week will have the forecast area in NW flow
aloft between a cool upper low over the Great Lakes and a very
warm ridge over the Rockies and Pacific Coast with mainly dry
weather.

FORECAST CONFIDENCE & DEVIATIONS:

Made minor tweaks to pops today and tonight with no other
changes to base NBM.

There is high confidence that Petroleum and Phillips Counties will
have precipitation at some point today and tonight with low
confidence in timing. Confidence in precipitation is low
elsewhere. There is high confidence in forecast temperatures over
the next 4 days and a cold front moving through on Monday night
into Tuesday.


&&

.AVIATION...
LAST UPDATED: 0815Z

FLIGHT CAT RANGE: VFR

DISCUSSION: Mid and high-level clouds will be over the region
today, tonight and Saturday. Isolated to scattered rain showers
will stay to the west and south of the airfields/terminals most of
the time. A shower tonight could reach as far east as KGGW and
KGDV.

WIND: Winds will be light and variable early. Then, the winds will
vary from NE, east to SE at 5 to 10 knots most of today and become
light and variable tonight.

EQUIPMENT: KGDV AWOS is currently not sending METARS. Amendments
will not be scheduled.


&&

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

$$

weather.gov/glasgow