013
FXUS65 KTFX 082149
AFDTFX

Area Forecast Discussion
National Weather Service Great Falls MT
249 PM MST Mon Dec 8 2025

.KEY MESSAGES...

 - Strong winds develop and become widespread across much of
   north-central and southwest Montana tonight through Tuesday
   morning.

 - Widespread above normal temperatures continue through Wednesday.

 - Precipitation is mainly focused along the continental divide through
   Tuesday where snow levels fluctuate at or above 6000 ft.

 - Precipitation and the potential for accumulating snowfall
   becomes more widespread across north-central Montana later
   this week as a colder airmass also moves back south into the
   region.

&&

.DISCUSSION...

 - Meteorological Overview:

A very active weather pattern continues through the week as a strong
westerly flow and plume of deep Pacific moisture remains oriented
across the Northern Rockies and MT with embedded disturbances
bringing multiple rounds of precipitation, initially focused along the
continental divide, but expanding further east across central and
north-central MT later this week. Meanwhile, mild Pacific air will
maintain above average temperatures and relatively high snow-levels
through the next few days before a much colder airmass surges back
south into north-central MT later this week.

Mid-level westerly flow increases further tonight as a shortwave
disturbance rapidly translates east from BC to AB with surface low
pressure emerging in southern AB and tracking across southern SK
Tuesday morning. Strong winds re-intensify this evening along the
Rocky Mtn Front with the arrival of 70-80kt 700mb winds and spread
east across north-central and central MT overnight tonight through
Tuesday morning. Temperatures will remain mild tonight with many
lower elevation areas seeing steady temperatures in the 40s as winds
increase and thick cloud-cover persists. Precipitation remains mainly
confined to areas along the continental divide through Tuesday
morning where snow levels currently around 6000 ft rise to 7000 ft
or more overnight, limiting any impactful snowfall to the highest
terrain above passes.

Winds shift more northwesterly on Tuesday behind the surface low
across eastern portions portions of north-central MT with enough
cooling aloft and weak instability present to support some
convective shower development, mainly across Hill/Blaine/Fergus
counties. Temperatures cool just enough in these areas Tuesday
afternoon to support snow or a mix of rain/snow with main impact
being brief visibility reduction in these showers.

Another embedded shortwave moves across the Northern Rockies
Wednesday with snow levels remaining high along the continental
divide where the bulk of the precipitation occurs, while a period
of lighter rain/snow shifts across the plains early Wednesday
before westerly flow spreads mild but windy conditions back east
across the area.

A colder airmass begins to spread back south into north-central MT
Wednesday night through Thursday with the colder air lingering
through at least Saturday morning before retreating back north.
Meanwhile, additional shortwave disturbance move across the region
with an east west frontal zone aloft becoming a focus for
precipitation Thursday and Friday. Latest model guidance trends
are supporting the potential for several inches of snow
accumulation across portions of north-central and central MT
Thursday and Friday with still a fair amount of uncertainty in
specific amounts. Hoenisch

 - Forecast Confidence & Scenarios:

Ingredients for mountain wave enhancement are focused mainly along
the Rocky Mountain Front this evening, shifting to areas adjacent to
the Little Belts across Judith Basin county late tonight through
Tuesday morning. Wind gusts in excess of 75 mph are likely along the
Rocky Mtn Front with a 30-40% chance of wind gusts reaching this
magnitude across Judith Basin County, where winds of this magnitude
are not as frequent and may be more impactful than those along the
Rocky Mtn Front.

The arrival of colder air later this week has seen some fluctuations
in timing with still considerable uncertainty in how far south the
cold air will penetrate beyond central MT. Most model guidance keeps
the colder airmass limited to the plains. By Friday it is
possible that locations on the plains see afternoon temperatures
in the single digits while southwest MT valley locations remain
above average with afternoon temperatures in the 40s. Hoenisch

&&

.AVIATION...
08/18Z TAF Period

VFR conditions will prevail across the KBZN, KEKS, and KHLN
terminals during this TAF Period. During the majority of this TAF
Period it will be very windy at all but the KHLN and KBZN
terminals. There will be several hours of wind gusts in excess of
50 kts at the KGTF, KEKS, and KCTB terminals after 09/06Z. There
will be instances of low-level wind shear and mountain wave
turbulence across North-central, Central, and Southwestern Montana
during the duration of this TAF Period. After 09/12Z across all
terminals there is greater than a 30% chance for rain and/or a
rain/snow mix. At the KHVR and KLWT terminals the rain and/or
rain/snow mix will lower visibility to at least MVFR-levels with a
10% chance for visibility to lower to IFR-levels or lower. During
the majority of this TAF Period there will be periods of mountain
obscuration across North-central, Central, and Southwestern
Montana. -IG

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  42  50  33  54 /  20  50  60  70
CTB  38  43  25  44 /  30  40  30  40
HLN  40  48  33  52 /  50  70  80  80
BZN  36  47  30  54 /  20  50  70  80
WYS  25  39  26  41 /  80  90  90  90
DLN  38  48  33  53 /  30  50  70  50
HVR  31  45  20  41 /  40  70  20  80
LWT  34  46  24  48 /  30  70  40  90

&&

.TFX WATCHES/WARNINGS/ADVISORIES...
High Wind Warning until 10 AM MST Tuesday for Cascade County
below 5000ft-East Glacier Park Region-Eastern Glacier, Western
Toole, and Central Pondera-Eastern Pondera and Eastern Teton-
Eastern Toole and Liberty-Gates of the Mountains-Madison River
Valley-Northern High Plains-Southern High Plains-Southern Rocky
Mountain Front-Upper Blackfoot and MacDonald Pass.

High Wind Warning from 6 PM this evening to 3 PM MST Tuesday for
Bears Paw Mountains and Southern Blaine-Big Belt, Bridger and
Castle Mountains-Fergus County below 4500ft-Hill County-Little
Belt and Highwood Mountains-Meagher County Valleys-Northern
Blaine County-Snowy and Judith Mountains-Western and Central
Chouteau County.

High Wind Warning until 3 PM MST Tuesday for Judith Basin County
and Judith Gap.

&&

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