857
FXUS65 KGGW 010941
AFDGGW

Area Forecast Discussion
National Weather Service Glasgow MT
Issued by National Weather Service Billings MT
341 AM MDT Tue Jul 1 2025

.DISCUSSION...

KEY MESSAGES:

- Hot and mainly dry weather is expected over the next few days. A
  Heat Advisory is in effect for most of northeast Montana for
  Wednesday.

- A more active weather pattern is expected to emerge for the
  second half of the week extending into the Independence Day
  holiday period with daily chances for showers and thunderstorms
  returning.

WEATHER PATTERN OVERVIEW:

An upper ridge continues building across the region with
daytime temperatures rising. Wednesday is expected to be the
hottest day, with high temperatures in the mid 90s to lower 100s.
These temperatures are already pushing toward Heat Advisory levels
with moderate to major heat risk. Temperatures could push
slightly higher with the 50th-75th percentile of the NBM
indicating more widespread readings at or above 100. Have gone
ahead and issued Heat Advisory for all but the easternmost zones
for Wednesday. Thursday afternoon looks to be a few degrees
cooler due to increased cloud cover.

Ensembles show upper ridging sliding east ahead of the next low
pressure system for the midweek. This will set up a more active
weather pattern with increased low-level moisture heading into the
4th of July holiday. In short, expect daily chances for
thunderstorms to return in the afternoon and evening hours
starting Wednesday night. Temperatures will also begin trending
cooler toward average.

FORECAST CONFIDENCE & DEVIATIONS:

The NBM was used for the forecast population with minimal
deviation needed to capture expected trends. Confidence is high on
mainly warm and dry weather through the next couple of days,
while currently medium for the occurrence of triple digit heat
midweek. Confidence is described as growing on increasing chances
for thunderstorms to return each day starting midweek.

&&

.AVIATION...
Flight Category: VFR

Discussion: High pressure across the area will mean mostly clear to
partly cloudy skies, with little to no daytime convective
development.

&&

.GGW WATCHES/WARNINGS/ADVISORIES...
Heat Advisory from 9 AM to 9 PM MDT Wednesday for Central and
Southeast Phillips-Central and Southern Valley-Dawson-Garfield-
McCone-Northern Phillips-Northern Valley-Petroleum-Prairie-
Southwest Phillips-Western Roosevelt.

&&

$$

weather.gov/glasgow