127
FXUS65 KTFX 300546
AFDTFX

Area Forecast Discussion
National Weather Service Great Falls MT
1046 PM MST Sat Nov 29 2025

Aviation Section Updated.

.KEY MESSAGES...

 - Coldest temperatures of the winter so far will remain through Monday
   morning with this afternoon through Sunday morning being the
   coldest.

 - Another system will bring widespread snowfall to the area
   Tuesday through Wednesday.

 - Monday through the end of the work week it will warm up.

&&

.UPDATE...
/Issued 841 PM MST Sat Nov 29 2025/

Not too many changes were made to the forecast tonight. Patchy
dense freezing fog has developed along parts of the Hi-line. Hi-
res guidance suggests fog/low stratus can continue to expand to
other parts of North-Central MT overnight. Current cold products
remain on track with a Cold Advisory in effect for Hill and
northern Blaine Counties tonight. There is a little uncertainty
how cold it gets overnight due to cloud cover. Models indicate
some cloud cover moving in overnight, which should keep the
apparent temperature to just at advisory level (up to -35 below).
However, if cloud cover doesn`t develop then areas across North-
Central MT may get a little bit colder than forecasted. Down
towards Southwest MT, there will be a slight chance for very light
snowfall through Sunday morning. -Wilson


&&

.DISCUSSION...
/Issued 841 PM MST Sat Nov 29 2025/

 - Meteorological Overview:

This afternoon an upper-level ridge will briefly move over North-
central, Central, and Southwestern Montana. It will be cold and
mostly dry this afternoon with isolated light snow across
Southwestern Montana late this afternoon through tonight. Due to
clearing skies tonight plus any melting snow fog is possible across
North-central Montana see the Forecast Confidence & Scenarios
Section for details. On Sunday an upper-level trough briefly moves
over North-central, Central, and Southwestern Montana. This will
bring another day of cold temperatures to the area with the coldest
temperatures of the year expected Sunday morning. Due to a surface
high exiting the area on Sunday it will be slightly warmer in the
afternoon than this afternoon. On Monday an upper-level ridge moves
over North-central, Central, and Southwestern Montana. This will
allow temperatures to warm up with mostly dry weather.

On Tuesday an upper-level trough will move over North-central,
Central, and Southwestern Montana. This will bring snow to North-
central, Central, and Southwestern Montana. On Wednesday the upper-
level trough remains over North-central, Central, and Southwestern
Montana. Snow will linger across the area on Wednesday. On Thursday
and Friday an upper-level ridge builds in over North-central,
Central, and Southwestern Montana this will allow temperatures to
warm up some more with mostly dry weather. IG

 - Forecast Confidence & Scenarios:

Across the plains of North-central Montana there is a 25 - 50%
chance for fog to form. The areas most susceptible to fog formation
are the milk river valley and any area where any snow melts.

Sunday morning there is greater than a 50% chance for subzero
temperatures across all of North-central Montana. Sunday morning
across the Milk River Valley there is greater than a 70% chance for
temperatures of 10 below zero or lower. Monday morning across the
Milk River Valley there is greater than a 60% chance for subzero
lows. On Sunday there is greater than a 50% chance for highs of 15
degrees or colder across North-central Montana north of a Great
Falls to Lewistown line. As a result a Cold Weather Advisory was
issued for Hill and Northern Blaine County from tonight through
Monday morning. IG

&&

.AVIATION...
30/06Z TAF Period

While VFR conditions are expected to prevail across North Central
and Southwestern Montana this evening, there are a few areas of
concern overnight tonight. First will be a possible area of fog
and/or low stratus across the Golden Triangle (KCTB, KHVR, KGTF)
that seems to be in the beginning stages of development. There
will also be a few light snow showers south of Interstate 90, but
any reductions in vis and/or ceilings here will be short lived.
Ludwig

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  -7  23   7  33 /   0   0   0   0
CTB -11  18   7  30 /   0   0   0   0
HLN   4  25   9  33 /   0   0   0   0
BZN   3  23   4  31 /  10  20   0   0
WYS   2  28   0  25 /  20  10   0  10
DLN  14  28  10  35 /  20  20   0   0
HVR -22   3 -10  26 /   0   0   0   0
LWT  -4  23   7  34 /   0   0   0   0

&&

.TFX WATCHES/WARNINGS/ADVISORIES...
Cold Weather Advisory until 10 AM MST Monday for Hill County-
Northern Blaine County.

&&

$$
http://www.weather.gov/greatfalls