811
FXUS65 KGGW 100515
AFDGGW

Area Forecast Discussion
National Weather Service Glasgow MT
1115 PM MDT Sun Aug 9 2026

.KEY MESSAGES...

- Seasonably warm temperatures are expected for Monday and
  Tuesday, along with an isolated to widely scattered afternoon
  and evening thunderstorm potential.

- A cooler and more unsettled weather pattern is likely to emerge
  starting midweek into the weekend with showers and thunderstorms
  expected at times each day. Some storms may produce beneficial
  rainfall.

&&

.DISCUSSION...

WEATHER PATTERN OVERVIEW:

Monday and Tuesday will feature seasonably warm temperatures
across NE Montana accompanied by isolated to widely scattered
afternoon and evening thunderstorms while ridging remains
pronounced across the Northern High Plains.

Toward the middle of the week a trough will dig into the Pacific
Northwest allowing the downstream ridge pattern to amplify as the
ridge axis pushes east. This will eventually send southwest flow
aloft over the region by the second half of the week into the
upcoming weekend. This pattern will lead to increasing daily
chances for showers and thunderstorms, with heavy rain potential
as the monsoonal fetch makes its way into the area. Bottom line:
cooler and more unsettled weather is likely to emerge by lateweek
into the weekend.
FORECAST CONFIDENCE & DEVIATIONS:

NBM was the guidance of choice for this forecast cycle which
captured expected macro trends well. Consensus has strong support
for seasonably warm temperatures to begin with this week before
conditions become cooler and more unsettled later in the week,
though there is divergence on how much QPF will ultimately land
which is expected at later time scales. Confidence should begin to
improve as this enters the short term and is picked up by higher
resolution guidance.


&&

.AVIATION...

LAST UPDATE: Sunday August 10 at 0500Z.

FLIGHT CAT RANGE: VFR.

DISCUSSION: Morning mid to high cloudiness will push east,
resulting in mostly sunny though hazy skies this afternoon. There
is a small chance for an isolated shower or thunderstorm during
the late afternoon an evening hours. While a storm tracking
directly over an area terminal could reduce visibility, it would
likely be brief.

WIND: Look for steady and persistent east winds, ranging from 5 to
15 kts, occasionally with stronger gusts.

&&

.GGW WATCHES/WARNINGS/ADVISORIES...
Lake Wind Advisory until 4 AM MDT Monday for Central and
Southeast Phillips-Central and Southern Valley-Garfield-McCone-
Petroleum.

&&

$$

weather.gov/glasgow