040
FXUS65 KGGW 142100
AFDGGW

Area Forecast Discussion
National Weather Service Glasgow MT
300 PM MDT Tue Jul 14 2026

.KEY MESSAGES...

- Dangerous heat will continue in the SE into Wednesday with an
  Extreme Heat Warning for Richland, Dawson, Prairie and Wibaux
  Counties through Wednesday night. Will have an Heat Advisory for
  most of the remainder of NE Montana through 2 am Wednesday.

- Scattered severe thunderstorms will move northeast, affecting
  the western and northern zones. Large hail, damaging winds and
  heavy rain are the greatest threats.

- Flood watch for flash flooding in effect tonight for Petroleum
  and southern and central Phillips Counties.


&&

.DISCUSSION...

WEATHER PATTERN OVERVIEW:
A strong easterly flow from the surface up to the mid levels this
afternoon is drawing in a very warm and humid airmass. Precip
Water, which is a measure of moisture in the atmospheric column,
is approaching record levels. This means there is the potential
for flooding with heavy rain. This looks best to occur from
central Phillips county into Petroleum counties, where a Flood
Watch is currently in effect from 9 pm till 6 am Wednesday.

The disturbance that will ignite the storms is embedded in a
southwest upper flow. Daytime heating has allowed cumulus clouds
to develop over the higher terrain to our southwest (western WY
north into central MT). These will move northeast and likely tap
into the 2000-3000 j/kg of CAPE over eastern Montana to bring
large hail, damaging winds and heavy rain, mainly 8 pm-midnight
this evening.

East to NE winds will remain strong enough through tonight for a
Lake Wind Advisory over Fort Peck Lake.

Wednesday and beyond: an upper low over the Pacific NW moves NE
into the Prairie Provinces of Canada while the upper ridge
rebounds over eastern Montana. This should keep temps warmer than
normal with small chances for showers and storms.

FORECAST CONFIDENCE & DEVIATIONS:

Tweaked pops at times tonight and Wednesday to provide better hour
to hour consistency. Otherwise, did not deviate from NBM. TFJ

&&

.AVIATION...

UPDATED: 2100Z

FLIGHT CATEGORY: VFR most of the time. KGGW & KOLF may have
periods of MVFR conditions at times late tonight.

DISCUSSION: Clouds will continue to increase into the early
evening hours while showers and thunderstorms move northeast,
affecting KGGW and KOLF after 02z.

SFC WIND: Generally E to NE at 15 to 20 knots with higher gusts
into the evening but thunderstorms will could bring gusty and
erratic winds for mainly KGGW and KOLF.

&&

.GGW WATCHES/WARNINGS/ADVISORIES...
Heat Advisory until 2 AM MDT Wednesday for Central and Southeast
Phillips-Central and Southern Valley-Eastern Roosevelt-Garfield-
McCone-Northern Phillips-Northern Valley-Petroleum-Southwest
Phillips-Western Roosevelt.

Lake Wind Advisory until noon MDT Wednesday for Central and
Southeast Phillips-Central and Southern Valley-Garfield-McCone-
Petroleum.

Flood Watch from 9 PM MDT this evening through late tonight for
Central and Southeast Phillips-Petroleum-Southwest Phillips.

Extreme Heat Warning until 2 AM MDT Thursday for Dawson-Prairie-
Richland-Wibaux.

&&

$$

weather.gov/glasgow