420
FXUS65 KGGW 130818
AFDGGW

Area Forecast Discussion
National Weather Service Glasgow MT
218 AM MDT Sun Jul 13 2025

.DISCUSSION...

KEY MESSAGES:

1) Hot and dry conditions continue today.

2) Chances for showers and thunderstorms start tonight in the
north and become widespread across the region Monday night and
continues through at least Tuesday night.

3) Cooler temperatures start in the north on Monday and spread to
the entire area on Tuesday and Wednesday.

WEATHER PATTERN OVERVIEW:
Hot and dry weather will prevail over NE Montana today. Meanwhile,
models and ensembles wants to bring a back door cold front at
least part way through the forecast area in the late afternoon and
early evening with gusty NE winds mainly north of the Missouri
River this evening and a chance of showers and thunderstorms north
of the Missouri River tonight. Not sure how much of these NE winds
will reach Fort Peck Lake this evening. Will hold off on a Lake
Wind Advisory for now.

This frontal boundary will be quasi-stationary over the forecast
area for most of the day on Monday. This will result in highs in
the 80s north and 90s south. Models and ensembles have differences
on where the front will be stationary Monday morning and when and
how quickly it moves south as a cold front Monday afternoon and
evening as a shortwave trough approaches the area from the west.
Chances for showers and thunderstorms will remain north of the
Missouri River during the day on Monday but will spread to the
entire region and become likely Monday night as the cold front
moves to the south.

The upper trough will keep frequent chances for showers and
thunderstorms over the area on Tuesday, Tuesday night, and
Wednesday with cooler than normal temperatures for mid July.
The highest QPF is expected Monday night through Tuesday night.
Portions of NE Montana could see precipitation amounts range
between 0.25" and 0.50" during this period.

FORECAST CONFIDENCE & DEVIATIONS:

Confidence is high that hot and dry conditions will continue
today. Confidence is low on temperatures on Monday due to the
uncertainty of the location of the frontal boundary. Confidence
is high on the cool and wet weather that starts Monday night and
continues until Tuesday night or Wednesday. While NBM was largely
followed, a blend with NBM 90 was used for winds this evening and
again Monday night as models frequently underforecast winds behind
a cold front.


&&

.AVIATION...

LAST UPDATED: 0820Z on July 13, 2025

FLIGHT CAT RANGE: VFR.

DISCUSSION: VFR conditions are expected with mostly clear skies
today and a mix of mid and high clouds tonight. KGGW and KOLF
could have an isolated shower or thunderstorm late tonight.
Otherwise, chances for showers and thunderstorms will remain north
of the TAF sites tonight.

WINDS: Light and variable this morning becoming west to SW 5 to 10
knots this afternoon. Around 00z, winds will veer to the north and
NE and increase to 10 to 20 knots at KGGW and KOLF, and 10 to 15
knots at KSDY. Meanwhile, winds will veer to the west and NW at
KGDV at 10 to 15 knots. NE winds will diminish to 5 to 10 knots
after 06z at KGGW, KOLF and KSDY and become light and variable at
KGDV.


&&

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

$$

weather.gov/glasgow