Bloomfield, Montana Weather Forecast Discussion

203
FXUS65 KGGW 230812
AFDGGW
Area Forecast Discussion
National Weather Service Glasgow MT
212 AM MDT Tue Sep 23 2025
.DISCUSSION...
KEY MESSAGES:
- Several days of dry weather is expected.
- Warmer temperatures are expected today and Wednesday followed by
  somewhat cooler temperatures Thursday and Friday.
- South winds on Wednesday may reach Lake Wind Advisory criteria.
WEATHER PATTERN OVERVIEW:
An upper ridge over the Pacific NW will expand into Montana today
and Wednesday. This will bring dry weather with warmer
temperatures today and Wednesday. The upper upper trough that was
over Montana on Monday moved to the south overnight. This trough
will be over Colorado today and form the eastern low on a quasi
omega block with another low off the southern California coast.
The northern end of the upper ridge will be along the US/Canada
border with fast zonal flow just to the north of the ridge over
Canada. Southerly winds will increase over the area on Wednesday
with very warm temperatures for late September which will be in
the 80s in most areas. There is about a 10 percent chance at this
point that the winds will be strong enough for a Lake Wind
Advisory on Wednesday.
A wave on this zonal flow aloft will flatten the ridge enough
Wednesday night to allow a weak cold front through the forecast
area with somewhat cooler temperatures on Thursday. An dry upper
trough on Friday will cool temperatures a few more degrees.
The ridge returns over the weekend with warmer temperatures.
FORECAST CONFIDENCE & DEVIATIONS:
Very high confidence on the dry weather for several days and the
very warm temperatures on Wednesday.
Low confidence on the speed of the southerly winds on Wednesday
and whether they will be strong enough for a Lake Wind Advisory.
No deviations from the NBM at this time.
&&
.AVIATION...
UPDATE: 0815Z, September 23
FLIGHT CAT RANGE: VFR
DISCUSSION: Mostly clear skies will be over the region today and
tonight with a few daytime cumulus this afternoon.
WIND: Light and variable winds most of the time today and tonight
except for KGGW which will have south winds 5 to 10 knots this
afternoon and SE winds 5 to 10 knots tonight.
EQUIPMENT: KSDY AMD NOT SKED will remain in place
until METARs comms issue is repaired.
&&
.GGW WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
weather.gov/glasgow

NWS GGW Office Area Forecast Discussion