190
FXUS65 KGGW 011842
AFDGGW

Area Forecast Discussion
National Weather Service Glasgow MT
1242 PM MDT Mon Jun 1 2026

.KEY MESSAGES...

- Periods of showers and isolated thunder will continue at times
  again through Wednesday.

- Lake Wind Advisory for Fort Peck Lake remains in effect until 6
  PM Today.

- The upper low will shift east on Wednesday with a brief dry
  window Wednesday evening into early Thursday. The next system
  will quickly approach from the west for a chance of
  thunderstorms Thursday afternoon & evening.


&&

.DISCUSSION...

WEATHER PATTERN OVERVIEW:
The slow moving upper low will continue to bring cool and wet
conditions to NE Montana over the next couple of days. Look for
periods of showers and an isolated thunderstorm to continue at
times through at least Wednesday. Wednesday evening will see the
low shift east with drying weather conditions.

For Thursday, the next shortwave will track in from the west with
the next round of thunderstorms. Some of the storms in the
afternoon and evening may offer heavy rainfall. The potential for
a few stronger storms will also be monitored as the high
resolution model guidance better handles this in the coming days.

Ensembles are also indicating warmer temperatures to return to the
region for the second half of the week once that disturbance
tracks east and the ridge axis becomes anchored over eastern
Montana.


FORECAST CONFIDENCE & DEVIATIONS:
NBM was well suited to handle the forecast this cycle which
captured overall expected trends well. In the coming days,
refining the finer details surrounding pops and thunderstorm
chances for Thursday may be appropriate.

Confidence otherwise remains above average on cool and wet
conditions at times through the middle of the week given excellent
ensemble consensus. There is also increasing concern with regard
to the next chance for thunderstorms across the area for Thursday.

GAH


&&

.AVIATION...
LAST UPDATED: 1615Z

FLIGHT CATEGORY: VFR to MVFR.

DISCUSSION: Periods of showers and isolated thunder will continue
to bring downpours that reduce visibility for KGGW and KOLF today.
Other terminals will remain dry until this evening at which point
a wave of showers and thunderstorms will make its way up the
yellowstone valley this evening into tonight clearing out about
15Z tomorrow. MVFR ceilings are expected to maintain at KGGW and
KOLF through the cycle.

WIND: W to SW at 10 to 20 gust 30 kts into the afternoon for all
terminals and lasting overnight and into Tuesday afternoon for
KOLF and KGGW. Calming to 10 kts or less at KSDY and KGDV
overnight and lasting through Tuesday afternoon.

GAH


&&

.GGW WATCHES/WARNINGS/ADVISORIES...
Lake Wind Advisory until 6 PM MDT this evening for Central and
Southeast Phillips-Central and Southern Valley-Garfield-McCone-
Petroleum.


&&

$$

weather.gov/glasgow