691
FXUS65 KGGW 192057
AFDGGW

Area Forecast Discussion
National Weather Service Glasgow MT
257 PM MDT Sat Apr 19 2025

.DISCUSSION...

KEY MESSAGES:

* Dry and breezy conditions present elevated fire weather concern
  today.

* The next low pressure system is approaching from the west.
  Expect some light rain tonight through Sunday morning and some
  more widespread rain Sunday night through Monday.

WEATHER PATTERN OVERVIEW:

A short-lived strong ridge of high pressure centered directly
through NE Montana today has lead to some very pleasant conditions
across the region.

The next storm system is a wide open Pacific trough from the
Canadian Rockies, and will likely impact our area with multiple
waves of rainfall - some light, and some heavier. The first wave
will be along and near the actually cool front or wind shift
tonight through early Sunday as it marches eastward. Model precip
data indicated that coverage will be spotty and timing will be
somewhat sporadic. But I settled on the best model consensus I
could find, while also compromising with neighboring area
forecasts. Expect trace amounts up to 0.05 inch.

The 2nd wave comes on a more pronounced and developed, embedded
short wave disturbance in the flow from late Sunday through late
Monday. Model precip data suggest that this will result in more
widespread greater rainfall accumulations - up to around 0.25 to
0.33 inch for many locations. Obviously, these details are subject
to change and will hone in on more accurate amounts as that time
approaches.

Tuesday and Wednesday, that low pressure trough will generally
give way to some weak ridging from the west and lessened chances
for rain.

Later next week, a generally unsettled weather pattern will
prevail over our region, bringing periodic chances for light rain
and seasonable temperatures.

FORECAST CONFIDENCE & DEVIATIONS:

Deviated from the NBM to alter rain chances through Sunday, and to
refine timing of those rain showers forced by a frontal passage.

Confidence remains high overall on the temperature pattern for
the next several days, while average or medium on measurable
precipitation amounts and timing early next week.



&&

.AVIATION...

LAST UPDATED: 2045Z, Saturday afternoon, April 19th

FLIGHT CAT RANGE: VFR through 08Z, then MVFR moves in from west
with rain showers through the remainder of this TAF cycle.

DISCUSSION: High pressure will give pleasant, mostly clear
conditions through this afternoon. A weak cold front will push
east tonight and bring overcast skies. Between 08-11Z early
Sunday, an area of MVFR/IFR ceilings and scattered rain showers
likely starts to impact KGGW and KOLF. Expect similar conditions
for KGDV and KSDY between 16-23Z later on Sunday.

WIND: Ahead of the front today from the SW around 15 kts with a
few stronger gusts. Behind the front tomorrow, from the N/NE
around 10 kts.




&&

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

$$

weather.gov/glasgow