882
FXUS65 KTFX 271755
AFDTFX

Area Forecast Discussion
National Weather Service Great Falls MT
1055 AM MST Thu Nov 27 2025

Aviation Section Updated.

.KEY MESSAGES...

 - Snow develops across north-central Montana this afternoon and
   intensifies overnight, spreading into southwest Montana by
   early Friday morning.

 - Gusty north winds and falling temperatures follow the passage
   of a cold front Thursday night through Friday with areas of
   blowing and drifting snow.

 - Coldest air of the season so far will arrive this weekend.

&&

.UPDATE...
/Issued 819 AM MST Thu Nov 27 2025/

Snow will begin along the Rocky Mountain Front this morning and
then spread south and east to much of North-central Montana by
this evening. Temperatures will then fall tonight behind a cold
front that will bring another round of snow with north winds to
North-central Montana. For the update high temperatures across the
Hi-Line were decreased to better reflect current observations and
trends. QPF grids were tweaked to reflect the latest hi-res model
guidance. The rest of the forecast is on track. -IG

&&

.DISCUSSION...
/Issued 819 AM MST Thu Nov 27 2025/

 - Meteorological Overview:

Warm advection ahead of an incoming Pacific shortwave will generate
some light snow or flurries as it lifts through the area Thursday
with steadier snow developing across northwest portions of north-
central MT as front stalls late Thursday afternoon and evening. Snow
intensifies along the west-east frontal zone Thursday night with
the latest models showing the potential for heavy snow across a
broader area of north-central Montana. Additional shortwave
energy arriving from the west and dropping south from Canada will
sweep southeast through the Northern Rockies and MT late Thursday
night through Friday, bringing a more widespread snowfall with
areas of upslope- enhanced snow lingering into Friday evening
across eastern portions of central and southwest MT before ending.

Surface high pressure and a colder airmass surges south from AB
Thursday night with gusty north winds developing overnight and
spreading through southwest MT on Friday. The combination of falling
snow and gusty north winds will add to potential travel hazards on
Friday. Temperatures fall to the teens and twenties following the
frontal passage, which occurs early Friday morning across north-
central and central MT but may not be until Friday afternoon across
southern portions of southwest MT.

The cold airmass settles across the region this weekend with mainly
dry conditions expected through Monday. Overnight low
temperatures in the single digits above/below zero are expected
Saturday morning and again Sunday morning with afternoon
temperatures in the teens and low twenties. Temperatures look to
moderate some next week but an unsettled northwest flow persists
with additional opportunities for snow by the middle of next week.
Hoenisch/thor


 - Forecast Confidence & Scenarios:

In many ways the forecast remains the same, particularly along the
Hi-Line with heavier amounts still expected along the Highway 2
corridor. One of the bigger changes with this forecast package is
that the models have started to correct themselves back to
previous versions where heavier snow was found further south into
places such as Great Falls. While this change does maintain the
confidence to keep the current areas across north-central Montana
into a watch, there is still some uncertainty as to whether Winter
Storm criteria will be met. So for now, most of north-central
Montana will be left in a watch.

Meanwhile, the Northern Rockies zone into the Rocky Mountain
Front, including Marias Pass, Browning, and Cut Bank, continue to
have high confidence in significant snowfall amounts and impacts
starting earlier than other zones across the region. Given the
persistence in the models and high confidence in snowfall and
impacts, the decision was made to upgrade this area to a Winter
Storm Warning starting Thursday afternoon. Aside from raw snow
amounts, periods of heavy snowfall rates and gusty north winds may
create periods of significant visibility reduction in this area.
Motorists should be prepared for very difficult travel conditions
on Highway 2.

Additional Winter Weather Advisories were added to portions of
central and southwest Montana late Thursday into late Friday. Many
of these areas are still expected to experience travel impacts and
some locations such as Judith Basin and Fergus counties and
Bozeman Pass, may experience some periods of reduced visibility
due to blowing snow. But for right now there is not enough of a
threat to warrant issuing a Winter Storm Warning or adding them to
the current watch. That being said, if the heavier snow amounts
and stronger wind gusts start setting up further south in future
model runs then some of these zones may warrant an upgrade at a
later time.  -thor


&&

.AVIATION...
27/18Z TAF Period

Moisture in westerly flow aloft and a mid-level warm front lifting
across the region will provide broken mainly mid-level cloud-cover
with a few lower bases producing some flurries/sprinkles and
mountain top obscuration through this afternoon. CIGS lower
across north-central MT this evening as moisture increases along
the frontal zone with light snow becoming more widespread. A cold
front surges south across north-cetral MT late tonight through
Friday morning, shifting winds to the north and enhancing
snowfall with snow and lower CIGS spreading south through central
and southwest MT terminals Friday morning. Hoenisch

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  36  18  23   1 /  30  90 100  40
CTB  26  11  17  -8 /  70 100  90  20
HLN  42  19  26   3 /  30  70 100  30
BZN  44  24  33  -1 /  20  40  90  50
WYS  38  18  35  -2 /  40  20  80  60
DLN  46  28  41   8 /  10  20  60  20
HVR  21  14  22  -5 /  20  90 100  70
LWT  38  15  26   0 /  20  90 100  70

&&

.TFX WATCHES/WARNINGS/ADVISORIES...
Winter Storm Warning from 2 PM this afternoon to 5 PM MST Friday
for East Glacier Park Region-Eastern Glacier, Western Toole, and
Central Pondera-Northern High Plains.

Winter Storm Watch from 5 PM MST this afternoon through Friday
afternoon for Bears Paw Mountains and Southern Blaine-Cascade
County below 5000ft-Eastern Pondera and Eastern Teton-Eastern
Toole and Liberty-Hill County-Northern Blaine County-Southern
High Plains-Southern Rocky Mountain Front-Western and Central
Chouteau County.

Winter Weather Advisory from midnight tonight to 11 PM MST
Friday for Big Belt, Bridger and Castle Mountains-Elkhorn and
Boulder Mountains-Fergus County below 4500ft-Gallatin Valley-
Gates of the Mountains-Helena Valley-Judith Basin County and
Judith Gap-Little Belt and Highwood Mountains-Snowy and Judith
Mountains.

Winter Storm Watch from late tonight through Friday afternoon
for Upper Blackfoot and MacDonald Pass.

&&

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