121
FXUS65 KGGW 310552
AFDGGW

Area Forecast Discussion
National Weather Service Glasgow MT
1052 PM MST Thu Jan 30 2025

.DISCUSSION...

KEY MESSAGES:

1) A back door cold front will affect part of the northeast
Montana late tonight to begin a more active weather pattern.

2) Precipitation chances start on Friday in the north and Friday
night in all areas.

3) A strong Arctic cold front will move in on Saturday night and
stay over the region through much of next week.


WEATHER PATTERN OVERVIEW:
There is strong agreement among ensembles of a backdoor cold front
moving in late tonight, which will bring low to moderate
probabilities of precipitation along the MT/SK border through the
day Friday. There is high confidence this front will stall, become
a warm front, and progress eastward Friday night. The HRRR and HRW
FV3 are in agreement of mixed precipitation, in the form of
freezing rain, sleet, and rain, occurring through the late morning
on Saturday. There is low confidence freezing rain will accumulate
more than one hundredth of precipitation. As this activity ends, a
disturbance is expected to move through central and southern MT on
Saturday and bring a mix of rain and snow as surface temperatures
climb above freezing. On Saturday evening, an arctic front will
bring temperatures well below average. Sunday evening marks the
beginning of snow chances that will linger through much of next
week. There is low confidence on snowfall amounts beyond Sunday
evening. Cold weather products are also expected in the north on
Sunday morning, and other locations for Sunday night into Monday
morning.


FORECAST CONFIDENCE & DEVIATIONS:
There is moderate confidence on light snow occurring across the
far north on Friday, and mixed precipitation on Friday night.
There is high confidence of below average temperatures coming in
behind an Arctic front that will move into the are on Saturday
night.

Deviation toward raising POPs for the opportunity for mixed
precipitation moving through on Friday night. Also increased
southeast winds ahead of the warm frontal passage as well.


&&

.AVIATION...
LAST UPDATE: 0545Z

FLIGHT CAT RANGE: VFR - IFR

DISCUSSION: Amid a broad upper level ridge, a back door cold front
will affect TAF sites beginning after 08Z tonight. There is high
(80-90%) confidence TAF sites will see MVFR ceilings between 11Z
and 22Z. There is moderate (40%-60%) confidence that IFR ceilings
may be possible at KOLF and KSDY from 15-21Z. The window and
confidence for IFR has increased a bit in the last 6 hours.

WIND: Light and variable this evening. Becoming NE to E at 5 to
15 knots after 12Z. Veering farther E to SE at 15 to 20 knots
after 18Z. Calming slightly after sundown to 10 to 15 kts.

BEYOND THE CYCLE: There is moderate(40-70%) confidence for
FREEZING RAIN from roughly 07-18Z Saturday with all the terminals
being impacted for at least few hours as cold air exits slowly
east and a disturbance begins an overrunning event. This threat
should end around 18Z Saturday. Ice on runways may be possible if
not on wings.

GAH


&&

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

$$

weather.gov/glasgow