808
FXUS65 KGGW 261907
AFDGGW

Area Forecast Discussion
National Weather Service Glasgow MT
107 PM MDT Sat Sep 26 2026

.KEY MESSAGES...
- Gusty winds will slowly reduce through the day today.

- Highs will remain the 60s and 70s through the end of the coming
  work week.

- Possible rain showers in the southeast portions of the CWA
  Monday morning. Isolated Thunderstorms may be possible SE of
  the Yellowstone River.


&&

.DISCUSSION...

Synoptic Setup: Forecast begins with a ridge running from northern
Manitoba into Ontario and down the Mississippi Valley. It then
turns back west across the southern plains and into the Hot High
pressure over the SW. A broad trough over western half of Canada
has begun to break into two parts with the eastern trough running
down the Canadian plains and into the Dakotas. The western part begins
over roughly British Columbia and moves off shore of the Pacific
Northwest and northern California.

Today through Monday: A broad trough to the north and the Hot
High pressure to the south will force flow across Montana to
remain mostly zonal through these periods. This will bring some
mid to high clouds but leave mostly cooler temps in the wake of
the cold front this morning that will hold on through Monday. By
Monday morning a disturbance arrives in the flow that may have
some minor impacts of the SE side of the Yellowstone Valley with
a couple hundredths of an inch of rain.

Monday night into Wednesday: The western most trough will move
inland and dig into the Intermountain West and Four Corners. In
response the northern section of the flow will build up into a
ridge over Montana that will keep conditions mostly dry through
these periods. Tuesday specifically will need to monitored for
Fire Weather concerns due to Low RH and gusty winds as the ridge
begins to break down.

Wednesday night onwards: Flow will attempt to return to zonal
briefly. But, model ensembles begin to break apart on individual
waves within the flow with more GFS runs focused on a brief
ridge/trough couplet, while EC members slowly orientate flow more
to the northwest. Standard deviations amongst ensemble members
suggest that no particular run is favored. Therefore, confidence
in these periods is low with the expectation of changes in future
iterations of the forecast here onward.

FORECAST CONFIDENCE & DEVIATIONS:

No deviations to NBM were observed.


&&

.AVIATION...
LAST UPDATED: 1615Z

FLIGHT CAT RANGE: VFR

DISCUSSION: Skies will be SKC initially today. By the late
afternoon FEW/SCT mid to high clouds will move in.

SFC WIND: W-NW at 10 to 15 kt with gusts to 25 kt. Wind will
decrease in strength further to about 10 kt by this evening with
conditions becoming light and variable mid Sunday morning.

GAH


&&

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


&&

$$

weather.gov/glasgow