Sidney, Montana 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

782
FXUS65 KGGW 251834
AFDGGW

Area Forecast Discussion
National Weather Service Glasgow MT
1234 PM MDT Sat Jul 25 2026

.KEY MESSAGES...

- Hot high temperatures near 100 degrees are expected for today
  and Sunday. Look for little overnight recovery with lows tonight
  in the mid 60s to the mid 70s.

- Isolated to scattered dry thunderstorms are possible during this
  afternoon and evening. A few may be severe with particularly
  strong wind gusts in excess of 60 mph in the western part of the
  area.

- The hot and dry weather conditions will raise fire weather
  concerns at times over the next few days. A Red Flag Warning
  remains in effect for portions of the area for this afternoon
  and evening due to lightning.



&&

.DISCUSSION...

WEATHER PATTERN OVERVIEW:

Upper ridging over the western U.S. will remain the dominant force
this weekend with triple digit heat during the afternoon hours
today and Sunday. Low temperatures tonight will struggle to get
down to the mid 60s to mid 70s, making for uncomfortable sleeping
conditions for those without air conditioning. The Extreme Heat
Warning continues through 10pm Sunday.

There will be enough instability with a shortwave trough
approaching from the southwest this afternoon and evening to
initiate a few dry thunderstorms. HREF max ensemble wind gust
guidance continues to support the potential for damaging wind
gusts as a primary threat, further noting the inverted-v forecast
soundings across the area. A Red Flag Warning for fire zones 134,
135, 136, and 137 continues for this afternoon due to the
lightning risk on dry fuels. As an aside, haze and some smoke will
continue at times to be a problem from upstream wildfires.

Ensembles continue to show the hot temperatures continuing through
at least the early and middle part of next week, with highs in the
90s to around 100 degrees each day.

FORECAST CONFIDENCE & DEVIATIONS:

The only deviation was to expand the slight chance PoPs this
evening and overnight.

There is moderate to high confidence in the heat products through
tomorrow evening, and for thunderstorms to occur, especially in
the southwest tonight. There is low confidence on the exact
locations that a severe wind gust may occur though.

There is moderate to high confidence in smoke and haze reducing
visibility between 1 mile and 6 miles through tomorrow evening.
There is similar confidence in the Red Flag Warning for later
today.

&&

.AVIATION...
UPDATE TIME: Saturday July 25 at 1830Z.

FLIGHT CATEGORY: VFR prevailing, temporary MVFR possible with
visibility reductions in thunderstorms and in haze.

SYNOPSIS: Upper ridging will continue to provide hot temperatures
to the region. There is moderate to high confidence (50-80
percent) of haze and smoke impacting TAF sites from now through
12Z, and then a break between 12Z and 16Z, and then a more intense
push after that time. There is potential for visibility to come
down as low as 1 mile at times, but there is low (30 percent) confidence
in this scenario. A shortwave trough moving through the ridge
will aid in isolated to scattered thunderstorms from 01Z to around
09Z Sunday. Gusty winds are the primary hazard with this
activity.

DENSITY ALTITUDE: Issues are expected at times with high
temperatures near 100 today and Sunday.

WINDS: Light and variable becoming northwest at 7 to 16 knots
after 15Z Sunday.

&&

.GGW WATCHES/WARNINGS/ADVISORIES...
Extreme Heat Warning until 10 PM MDT Sunday for Central and
Southeast Phillips-Central and Southern Valley-Daniels-Dawson-
Eastern Roosevelt-Garfield-McCone-Northern Phillips-Northern
Valley-Petroleum-Prairie-Richland-Sheridan-Southwest Phillips-
Western Roosevelt-Wibaux.

Red Flag Warning from 4 PM this afternoon to 10 PM MDT this
evening for Northern Valley and Northern Phillips Counties-
Southern Petroleum and Southern Garfield Counties-The Little
Rockies-The Lower Missouri River Breaks including the Charles M
Russell National Wildlife Refuge.

&&

$$

weather.gov/glasgow