Winter Storm Warning 21, NWS Great Falls, MT

711 
WWUS45 KTFX 162141
WSWTFX

URGENT - WINTER WEATHER MESSAGE
National Weather Service Great Falls MT
241 PM MST Tue Dec 16 2025

MTZ301-307-171245-
/O.CON.KTFX.WS.W.0021.251217T0300Z-251218T0600Z/
East Glacier Park Region-Southern Rocky Mountain Front-
Including the following locations: Babb, Kiowa, Saint Mary, East
Glacier Park, Logan Pass, Marias Pass, and Rogers Pass
241 PM MST Tue Dec 16 2025

...WINTER STORM WARNING REMAINS IN EFFECT FROM 8 PM THIS EVENING TO 
11 PM MST WEDNESDAY...

* WHAT...Heavy snow expected. Total snow accumulations between 4 and 
  10 inches  at Marias Pass with higher amounts over the mountains 
  in Glacier National Park. Winds could gust over 70 mph at times.

* WHERE...The Continental Divide along the Rocky Mountain Front.

* WHEN...From 8 PM this evening to 11 PM MST Wednesday.

* IMPACTS...Travel could be very difficult to dangerous and tire 
  chains may be required for some vehicles. Visibility may drop 
  below 1/4 mile at times due to falling and blowing snow. Those in 
  the backcountry should ensure they are prepared for dangerous 
  conditions.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in 
your vehicle in case of an emergency. The latest road conditions can 
be obtained by calling 5 1 1 or visiting the MDT Road Report website.

Remember, a Winter Storm Warning means that there is at least an 80% 
chance of impactful winter weather conditions during the warning 
period.

&&

$$

MTZ317-327-329-330-171245-
/O.NEW.KTFX.WW.Y.0057.251217T0000Z-251218T0600Z/
Little Belt and Highwood Mountains-Northwest Beaverhead County-
Ruby Mountains and Southern Beaverhead Mountains-Gallatin and
Madison County Mountains and Centennial Mountains-
Including the following locations: Neihart, Monarch, Big Hole
Pass, Monida Pass, Raynolds Pass, Targhee Pass, Wisdom, Big Sky,
Chief Joseph Pass, Wise River, West Yellowstone, Dewey, and Kings
Hill Pass
241 PM MST Tue Dec 16 2025

...WINTER WEATHER ADVISORY IN EFFECT UNTIL 11 PM MST WEDNESDAY...

* WHAT...Snow expected. Total snow accumulations up to 6 inches. 
  Winds gusting as high as 75 mph.

* WHERE...The Mountains of Southwestern Montana south of Interstate 
  90, and Little Belt and Highwood Mountains.

* WHEN...Until 11 PM MST Wednesday.

* IMPACTS...Travel could be very difficult. Widespread blowing snow 
  could significantly reduce visibility. Very strong winds could 
  cause extensive tree damage.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. The latest road 
conditions can be obtained by calling 5 1 1 or visiting the MDT Road 
Report website.

Remember, a Winter Weather Advisory means that there is at least an 
80% chance of minor impacts due to winter weather conditions during 
the advisory period.

&&

$$

Ludwig

702 
WWUS45 KTFX 170926
WSWTFX

URGENT - WINTER WEATHER MESSAGE
National Weather Service Great Falls MT
226 AM MST Wed Dec 17 2025

MTZ301-307-172300-
/O.CON.KTFX.WS.W.0021.000000T0000Z-251218T0600Z/
East Glacier Park Region-Southern Rocky Mountain Front-
Including the following locations: Babb, Kiowa, East Glacier
Park, Logan Pass, Marias Pass, Rogers Pass, and Saint Mary
226 AM MST Wed Dec 17 2025

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 11 PM MST THIS 
EVENING...

* WHAT...Snow with a period of heavy snow this morning. Total snow 
  accumulations between 3 and 8 inches  at Marias Pass with higher 
  amounts over the mountains in Glacier National Park. Winds could 
  gust over 70 mph at times.

* WHERE...The Continental Divide along the Rocky Mountain Front.

* WHEN...Until 11 PM MST this evening.

* IMPACTS...Travel could be very difficult to dangerous and tire 
  chains may be required for some vehicles. Visibility may drop 
  below 1/4 mile at times due to falling and blowing snow. Those in 
  the backcountry should ensure they are prepared for dangerous 
  conditions.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in 
your vehicle in case of an emergency. The latest road conditions can 
be obtained by calling 5 1 1 or visiting the MDT Road Report website.

Remember, a Winter Storm Warning means that there is at least an 80% 
chance of impactful winter weather conditions during the warning 
period.

&&

$$

MTZ317-327-329-330-172300-
/O.CON.KTFX.WW.Y.0057.000000T0000Z-251218T0600Z/
Little Belt and Highwood Mountains-Northwest Beaverhead County-
Ruby Mountains and Southern Beaverhead Mountains-Gallatin and
Madison County Mountains and Centennial Mountains-
Including the following locations: Big Hole Pass, Monarch, West
Yellowstone, Wisdom, Wise River, Targhee Pass, Big Sky, Neihart,
Monida Pass, Dewey, Raynolds Pass, Chief Joseph Pass, and Kings
Hill Pass
226 AM MST Wed Dec 17 2025

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 PM MST THIS 
EVENING...

* WHAT...Snow. Additional snow accumulations up to 4 inches. Winds 
  gusting as high as 75 mph.

* WHERE...The Mountains of Southwestern Montana south of Interstate 
  90, and Little Belt and Highwood Mountains.

* WHEN...Until 11 PM MST this evening.

* IMPACTS...Plan on slippery road conditions developing this morning 
  over mountain passes. Blowing snow could significantly reduce 
  visibility. Very strong winds could cause extensive tree damage.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. The latest road 
conditions can be obtained by calling 5 1 1 or visiting the MDT Road 
Report website.

Remember, a Winter Weather Advisory means that there is at least an 
80% chance of minor impacts due to winter weather conditions during 
the advisory period.

&&

$$

Hoenisch

897 
WWUS45 KTFX 172125
WSWTFX

URGENT - WINTER WEATHER MESSAGE
National Weather Service Great Falls MT
225 PM MST Wed Dec 17 2025

MTZ301-307-180600-
/O.CON.KTFX.WS.W.0021.000000T0000Z-251218T0600Z/
East Glacier Park Region-Southern Rocky Mountain Front-
Including the following locations: East Glacier Park, Marias
Pass, Logan Pass, Saint Mary, Kiowa, Babb, and Rogers Pass
225 PM MST Wed Dec 17 2025

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 11 PM MST THIS 
EVENING...

* WHAT...Heavy snow. Additional snow accumulations up to 3 inches. 
  Winds gusting as high as 75 mph at times.

* WHERE...The Continental Divide along the Rocky Mountain Front.

* WHEN...Until 11 PM MST this evening.

* IMPACTS...Travel could be very difficult to dangerous and tire 
  chains may be required for some vehicles. Those in the backcountry 
  should ensure they are prepared for dangerous conditions.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in 
your vehicle in case of an emergency. The latest road conditions can 
be obtained by calling 5 1 1 or visiting the MDT Road Report website.

Remember, a Winter Storm Warning means that there is at least an 80% 
chance of impactful winter weather conditions during the warning 
period.

&&

$$

MTZ327-181300-
/O.NEW.KTFX.WW.Y.0058.251218T2100Z-251220T0400Z/
/O.CON.KTFX.WW.Y.0057.000000T0000Z-251218T0600Z/
Northwest Beaverhead County-
Including the following locations: Wisdom, Chief Joseph Pass,
Wise River, Dewey, and Big Hole Pass
225 PM MST Wed Dec 17 2025

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 PM MST THIS 
EVENING...
...WINTER WEATHER ADVISORY IN EFFECT FROM 2 PM THURSDAY TO 9 PM MST 
FRIDAY...

* WHAT...For the first Winter Weather Advisory, snow. Additional 
  snow accumulations up to two inches. Winds gusting as high as 55 
  mph. For the second Winter Weather Advisory, snow expected. Total 
  snow accumulations between 2 and 6 inches at lower elevations, 
  with snow in excess of a foot above pass level. Winds gusting as 
  high as 55 mph.

* WHERE...Northwest Beaverhead County.

* WHEN...For the first Winter Weather Advisory, until 11 PM MST this 
  evening. For the second Winter Weather Advisory, from 2 PM 
  Thursday to 9 PM MST Friday.

* IMPACTS...Travel could be very difficult and tire chains may be 
  required for some vehicles. Those in the backcountry should ensure 
  they are prepared for dangerous conditions. Widespread blowing 
  snow could significantly reduce visibility. Very strong winds 
  could cause extensive tree damage.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. The latest road 
conditions can be obtained by calling 5 1 1 or visiting the MDT Road 
Report website.

Remember, a Winter Weather Advisory means that there is at least an 
80% chance of minor impacts due to winter weather conditions during 
the advisory period.

&&

$$

MTZ305-306-180600-
/O.EXB.KTFX.WW.Y.0057.251217T2200Z-251218T0600Z/
Hill County-Northern Blaine County-
Including the following locations: Zurich, Hogeland, Havre, Fort
Belknap, Harlem, and Chinook
225 PM MST Wed Dec 17 2025

...WINTER WEATHER ADVISORY IN EFFECT UNTIL 11 PM MST THIS EVENING...

* WHAT...Snow expected. Total snow accumulations up to one inch. 
  Winds gusting as high as 75 mph. Brief reduction of visibility to 
  one-half mile or less due to the combination of falling snow and 
  winds.

* WHERE...Hill County and Northern Blaine County.

* WHEN...Until 11 PM MST this evening.

* IMPACTS...Plan on slippery road conditions. Areas of blowing snow 
  could significantly reduce visibility. Very strong winds could 
  cause extensive tree damage.

* ADDITIONAL DETAILS...The combination of falling snow and gusty 
  winds will result in greatly reduced visibility for an hour or two 
  this evening for the evening commute.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. The latest road 
conditions can be obtained by calling 5 1 1 or visiting the MDT Road 
Report website.

Remember, a Winter Weather Advisory means that there is at least an 
80% chance of minor impacts due to winter weather conditions during 
the advisory period.

&&

$$

MTZ317-329-330-180600-
/O.CON.KTFX.WW.Y.0057.000000T0000Z-251218T0600Z/
Little Belt and Highwood Mountains-Ruby Mountains and Southern
Beaverhead Mountains-Gallatin and Madison County Mountains and
Centennial Mountains-
Including the following locations: West Yellowstone, Monarch,
Monida Pass, Big Sky, Kings Hill Pass, Neihart, Raynolds Pass,
and Targhee Pass
225 PM MST Wed Dec 17 2025

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 PM MST THIS 
EVENING...

* WHAT...Snow. Additional snow accumulations up to one inch. Winds 
  gusting as high as 75 mph.

* WHERE...Little Belt and Highwood Mountains, Gallatin and Madison 
  County Mountains and Centennial Mountains, and Ruby Mountains and 
  Southern Beaverhead Mountains.

* WHEN...Until 11 PM MST this evening.

* IMPACTS...Plan on slippery road conditions. Widespread blowing 
  snow could significantly reduce visibility. Very strong winds 
  could cause extensive tree damage.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. The latest road 
conditions can be obtained by calling 5 1 1 or visiting the MDT Road 
Report website.

Remember, a Winter Weather Advisory means that there is at least an 
80% chance of minor impacts due to winter weather conditions during 
the advisory period.

&&

$$

AM

211 
WWUS45 KTFX 180057
WSWTFX

URGENT - WINTER WEATHER MESSAGE
National Weather Service Great Falls MT
557 PM MST Wed Dec 17 2025

MTZ301-307-180600-
/O.CON.KTFX.WS.W.0021.000000T0000Z-251218T0600Z/
East Glacier Park Region-Southern Rocky Mountain Front-
Including the following locations: Marias Pass, Logan Pass, Saint
Mary, East Glacier Park, Rogers Pass, Babb, and Kiowa
557 PM MST Wed Dec 17 2025

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL 11 PM MST THIS 
EVENING...

* WHAT...Heavy snow. Additional snow accumulations up to 3 inches. 
  Winds gusting as high as 75 mph at times.

* WHERE...The Continental Divide along the Rocky Mountain Front.

* WHEN...Until 11 PM MST this evening.

* IMPACTS...Travel could be very difficult to dangerous and tire 
  chains may be required for some vehicles. Those in the backcountry 
  should ensure they are prepared for dangerous conditions.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If you must travel, keep an extra flashlight, food, and water in 
your vehicle in case of an emergency. The latest road conditions can 
be obtained by calling 5 1 1 or visiting the MDT Road Report website.

Remember, a Winter Storm Warning means that there is at least an 80% 
chance of impactful winter weather conditions during the warning 
period.

&&

$$

MTZ311-314-318-180600-
/O.EXA.KTFX.WW.Y.0057.000000T0000Z-251218T0600Z/
Bears Paw Mountains and Southern Blaine-Fergus County below
4500ft-Snowy and Judith Mountains-
Including the following locations: Hilger, Lewistown, and Rocky
Boy
557 PM MST Wed Dec 17 2025

...WINTER WEATHER ADVISORY IN EFFECT UNTIL 11 PM MST THIS EVENING...

* WHAT...Snow. Additional snow accumulations up to one inch. Winds 
  gusting as high as 75 mph will result in at least patchy blowing 
  snow.

* WHERE...Snowy and Judith Mountains, Bears Paw Mountains and 
  Southern Blaine, and Fergus County below 4500ft.

* WHEN...Until 11 PM MST this evening.

* IMPACTS...Plan on slippery road conditions. Widespread blowing 
  snow could significantly reduce visibility. Very strong winds 
  could cause extensive tree damage.

* ADDITIONAL DETAILS...Visibility to around one-half mile or less at 
  times through 8 PM due to the falling snow. Patchy blowing snow 
  will persist through 11 PM.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. The latest road 
conditions can be obtained by calling 5 1 1 or visiting the MDT Road 
Report website.

Remember, a Winter Weather Advisory means that there is at least an 
80% chance of minor impacts due to winter weather conditions during 
the advisory period.

&&

$$

MTZ327-181600-
/O.CON.KTFX.WW.Y.0057.000000T0000Z-251218T0600Z/
/O.CON.KTFX.WW.Y.0058.251218T2100Z-251220T0400Z/
Northwest Beaverhead County-
Including the following locations: Wise River, Chief Joseph Pass,
Wisdom, Big Hole Pass, and Dewey
557 PM MST Wed Dec 17 2025

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 PM MST THIS 
EVENING...
...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 2 PM THURSDAY TO 9 
PM MST FRIDAY...

* WHAT...For the first Winter Weather Advisory, snow. Additional 
  snow accumulations up to two inches. Winds gusting as high as 55 
  mph. For the second Winter Weather Advisory, snow expected. Total 
  snow accumulations between 2 and 6 inches at lower elevations, 
  with snow in excess of a foot above pass level. Winds gusting as 
  high as 55 mph.

* WHERE...Northwest Beaverhead County.

* WHEN...For the first Winter Weather Advisory, until 11 PM MST this 
  evening. For the second Winter Weather Advisory, from 2 PM 
  Thursday to 9 PM MST Friday.

* IMPACTS...Travel could be very difficult and tire chains may be 
  required for some vehicles. Those in the backcountry should ensure 
  they are prepared for dangerous conditions. Widespread blowing 
  snow could significantly reduce visibility. Very strong winds 
  could cause extensive tree damage.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. The latest road 
conditions can be obtained by calling 5 1 1 or visiting the MDT Road 
Report website.

Remember, a Winter Weather Advisory means that there is at least an 
80% chance of minor impacts due to winter weather conditions during 
the advisory period.

&&

$$

MTZ305-306-180600-
/O.CON.KTFX.WW.Y.0057.000000T0000Z-251218T0600Z/
Hill County-Northern Blaine County-
Including the following locations: Zurich, Chinook, Fort Belknap,
Havre, Harlem, and Hogeland
557 PM MST Wed Dec 17 2025

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 PM MST THIS 
EVENING...

* WHAT...Snow expected. Total snow accumulations up to one inch. 
  Winds gusting as high as 75 mph. Brief reduction of visibility to 
  one-half mile or less due to the combination of falling snow and 
  winds.

* WHERE...Hill County and Northern Blaine County.

* WHEN...Until 11 PM MST this evening.

* IMPACTS...Plan on slippery road conditions. Areas of blowing snow 
  could significantly reduce visibility. Very strong winds could 
  cause extensive tree damage.

* ADDITIONAL DETAILS...The combination of falling snow and gusty 
  winds will result in greatly reduced visibility for an hour or two 
  this evening for the evening commute.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. The latest road 
conditions can be obtained by calling 5 1 1 or visiting the MDT Road 
Report website.

Remember, a Winter Weather Advisory means that there is at least an 
80% chance of minor impacts due to winter weather conditions during 
the advisory period.

&&

$$

MTZ317-329-330-180600-
/O.CON.KTFX.WW.Y.0057.000000T0000Z-251218T0600Z/
Little Belt and Highwood Mountains-Ruby Mountains and Southern
Beaverhead Mountains-Gallatin and Madison County Mountains and
Centennial Mountains-
Including the following locations: Raynolds Pass, Neihart,
Targhee Pass, Monarch, Monida Pass, West Yellowstone, Big Sky,
and Kings Hill Pass
557 PM MST Wed Dec 17 2025

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 PM MST THIS 
EVENING...

* WHAT...Snow. Additional snow accumulations up to one inch. Winds 
  gusting as high as 70 mph.

* WHERE...Little Belt and Highwood Mountains, Gallatin and Madison 
  County Mountains and Centennial Mountains, and Ruby Mountains and 
  Southern Beaverhead Mountains.

* WHEN...Until 11 PM MST this evening.

* IMPACTS...Plan on slippery road conditions developing this morning 
  over mountain passes. Blowing snow could significantly reduce 
  visibility. Very strong winds could cause extensive tree damage.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. The latest road 
conditions can be obtained by calling 5 1 1 or visiting the MDT Road 
Report website.

Remember, a Winter Weather Advisory means that there is at least an 
80% chance of minor impacts due to winter weather conditions during 
the advisory period.

&&

$$

AM

068 
WWUS45 KTFX 180229
WSWTFX

URGENT - WINTER WEATHER MESSAGE
National Weather Service Great Falls MT
729 PM MST Wed Dec 17 2025

MTZ301-307-180330-
/O.CAN.KTFX.WS.W.0021.000000T0000Z-251218T0600Z/
East Glacier Park Region-Southern Rocky Mountain Front-
Including the following locations: Marias Pass, Logan Pass, Saint
Mary, East Glacier Park, Rogers Pass, Babb, and Kiowa
729 PM MST Wed Dec 17 2025

...WINTER STORM WARNING IS CANCELLED...

While lingering light snow will remain for a few more hours, the 
threat for widespread impactful snow has diminished.

$$

MTZ327-181730-
/O.CAN.KTFX.WW.Y.0057.000000T0000Z-251218T0600Z/
/O.CON.KTFX.WW.Y.0058.251218T2100Z-251220T0400Z/
Northwest Beaverhead County-
Including the following locations: Wise River, Chief Joseph Pass,
Wisdom, Big Hole Pass, and Dewey
729 PM MST Wed Dec 17 2025

...WINTER WEATHER ADVISORY REMAINS IN EFFECT FROM 2 PM THURSDAY TO 9 
PM MST FRIDAY...
...WINTER WEATHER ADVISORY IS CANCELLED...

* WHAT...Snow expected. Total snow accumulations between 2 and 6 
  inches at lower elevations, with snow in excess of a foot above 
  pass level. Winds gusting as high as 55 mph.

* WHERE...Northwest Beaverhead County.

* WHEN...From 2 PM Thursday to 9 PM MST Friday.

* IMPACTS...Travel could be very difficult and tire chains may be 
  required for some vehicles. Those in the backcountry should ensure 
  they are prepared for dangerous conditions. Strong winds could 
  cause tree damage.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. The latest road 
conditions can be obtained by calling 5 1 1 or visiting the MDT Road 
Report website.

Remember, a Winter Weather Advisory means that there is at least an 
80% chance of minor impacts due to winter weather conditions during 
the advisory period.

&&

$$

MTZ317-329-330-180330-
/O.CAN.KTFX.WW.Y.0057.000000T0000Z-251218T0600Z/
Little Belt and Highwood Mountains-Ruby Mountains and Southern
Beaverhead Mountains-Gallatin and Madison County Mountains and
Centennial Mountains-
Including the following locations: Raynolds Pass, Neihart,
Targhee Pass, Monarch, Monida Pass, West Yellowstone, Big Sky,
and Kings Hill Pass
729 PM MST Wed Dec 17 2025

...WINTER WEATHER ADVISORY IS CANCELLED...

While lingering light snow will remain for a few more hours, the 
threat for widespread impactful snow has diminished.

$$

MTZ305-306-311-314-318-180600-
/O.CON.KTFX.WW.Y.0057.000000T0000Z-251218T0600Z/
Hill County-Northern Blaine County-Bears Paw Mountains and
Southern Blaine-Fergus County below 4500ft-Snowy and Judith
Mountains-
Including the following locations: Zurich, Chinook, Fort Belknap,
Lewistown, Havre, Harlem, Hilger, Hogeland, and Rocky Boy
729 PM MST Wed Dec 17 2025

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 11 PM MST THIS 
EVENING...

* WHAT...Snow. Additional snow accumulations up to one-half inch. 
  Winds gusting as high as 70 mph. Patchy blowing snow may result in 
  greatly reduced visibility.

* WHERE...Snowy and Judith Mountains, Bears Paw Mountains and 
  Southern Blaine, Fergus County below 4500ft, Hill County, and 
  Northern Blaine County.

* WHEN...Until 11 PM MST this evening.

* IMPACTS...Plan on slippery road conditions. Areas of blowing snow 
  could significantly reduce visibility. Very strong winds could 
  cause extensive tree damage.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Slow down and use caution while traveling. The latest road 
conditions can be obtained by calling 5 1 1 or visiting the MDT Road 
Report website.

Remember, a Winter Weather Advisory means that there is at least an 
80% chance of minor impacts due to winter weather conditions during 
the advisory period.

&&

$$

AM

Area Forecast Discussion
National Weather Service Great Falls MT
743 PM MST Mon Dec 15 2025

.KEY MESSAGES...

- Strong, gusty winds peak along the Rocky Mountain Front this
  afternoon and then over central and north-central Montana later
  this evening through early Tuesday.

- A dynamic Pacific front brings widespread strong to damaging
  winds and locally intense snow showers on Wednesday.

- The colder air sags southward into north-central Montana for the
  second half of the week while mostly mountain snow.

&&

.UPDATE...

Evening update has been published, with the main adjustment being
to increase low temperatures overnight given the strong winds,
especially over the plains. The other adjustment was to add the
Madison River Valley to the High Wind Warning given Norris Hill
verifying on both high sustained and wind gusts. Otherwise the
remainder of the forecast remains on track, with high winds
overspreading the remainder of the plains during the overnight
hours tonight. - Moldan

&&

.DISCUSSION...
/Issued 424 PM MST Mon Dec 15 2025/

 - Meteorological Overview:

Weak ridging aloft will maintain well above normal temperatures
today while strong cross barrier flow and mountain wave activity
maintain periods of strong, gusty winds along the Rocky Mountain
Front and much of north-central MT through Tuesday morning. H700
flow will roughly run between 60 and 80 kts with mountain waves
transferring the strongest winds to the surface along the Rocky
Mountain Front through this evening and a shortwave passage
bringing peak winds over the plains this evening through early
Tuesday.

Height falls and cooling aloft will bring slightly cooler, but
still above average temperatures on Tuesday with winds diminishing
some by the afternoon hours. Pacific moisture streaming towards
the Continental Divide will bring periods of light snow to the
immediate eastern slopes of the Rocky Mountain Front. Otherwise,
Tuesday looks rather tranquil compared to what's coming on
Wednesday.

The well advertised potent Pacific trough and attendant cold
front is still progged to sweep through the state on Wednesday and
bring at least a several hour period of widespread strong, to
damaging winds. This system will be driven by strong cold air
advection and H850/H700 flow in the 55 to 85 kt range, both of
which look to occur during peak diurnal mixing. The sharp
frontogenesis with this system quickly drops H700/H500
temperatures to around -15C/-30C behind the front, encouraging
scattered locally intense snow shower/squall development. The
central and southwest mountain passes look to be the target for
the most impacts from this convective snow activity Wednesday
morning/early afternoon and then it shifts to along the Hi- Line
in the evening hours per the Canadian Front. There will also be
ongoing snow along the higher terrain of the Rocky Mountain Front
that become heavy at times Tuesday night into Wednesday,
particularly above pass level.

Colder air will briefly clip northern areas on Thursday in the
wake of the passing trough/cold front before milder air moves back
in ahead of the next Pacific trough. There will be a couple of
Pacific troughs that traverse the Northern Rockies through early
next week. Each will bring a period of increased mostly mountain
snow followed by modest intrusions of Arctic air, primarily
clipping northern areas. Timing for these trough/cold fronts look
to be late Thursday through early Saturday and again Sunday into
Monday. - RCG

 - Forecast Confidence & Scenarios:

Periods of strong winds along the Rocky Mountain Front and
central/north-central MT through Tuesday morning...

Strongest winds this afternoon will continue to favor the Rocky
Mountain Front and the plains along and west of highway 89 where
wind gusts are exceeding the 75 to 90 mph range at times. The
normally wind prone locations such as Bynum, Deep Creek, and East
Glacier/Browning areas will be most prone to gusts exceeding 90 mph.
Farther east, the strongest winds look to occur with the ejecting
shortwave trough this evening through early Tuesday when 50 to 70
mph gusts will be more common.

The main uncertainty with this event is the nighttime peak of upper
level winds possibly reducing the occurrence of stronger gusts
mixing to the surface. This will be most pronounced over some of the
more wind protected valleys, including the Milk River Valley
vicinity. Higher end probabilities (70%+) for gusts over 55 mph are
a little spottier here, but given some of these areas already
reached high wind criteria and the upper level flow strengthens
tonight during the shortwave passage, at least localized warning
criteria gusts seem plausible. The secondary uncertainty will be
central and southern areas along and north of the I90 corridor. Some
of these mountain passes may have brief periods with gusts exceeding
60 mph as will the Canyon Ferry area. Left these locations out of
the warning for now given limited opportunity and lower end
probabilities (generally less than 50%) for gusts over 55 mph.

Impacts will continue to include difficult to dangerous travel
for high profile vehicles, localized blowing dust near open
fields, and the movement of unsecured outdoor items, including
Christmas decorations. Additional power outages also can't ruled
out, particularly for areas that observe the higher end gusts.

Widespread strong to damaging winds and localized intense snow
showers/squall on Wednesday...

Conditions continue to be favorable for a widespread strong to
damaging wind event across southwest and central/north-central MT on
Wednesday. Strong cold air advection and peak H700 flow in the 60 to
90 kt range looking to occur during maximum diurnal mixing is
concerning at this point to say the least. Some caveats that would
weaken or preclude the winds such as a stronger/faster Canadian
front undercutting the strong winds aloft and shifts in frontal
passage timing are starting to lose steam. Just of note, H850 winds
behind the Canadian front are now highlighting north/northwesterly
H850 winds in excess of 50 kts. Additionally, this event look to be
of longer duration (multiple hours of very windy conditions vs the
typical 1-3 hr peak period). Given the wide swath of 60 to 80 mph
wind gusts expected, impacts look to include difficult to dangerous
travel for high profile vehicles, downed trees/property damage, and
scattered power outages. All the watches for Wednesday have been
upgraded to a warnings and now include the entire forecast area.
In addition to the winds, there will be sufficient instability and
dynamics for locally intense snow shower/squalls, particularly
for central and southwest Montana. Moderate to heavy snow will
also be ongoing along the higher terrain of the Northern Rocky
Mountain Front and a brief period of gusty accumulating snow may
even work its way southward to the Hi-Line Wednesday evening via
the Canadian cold front. - RCG

&&

.AVIATION...
16/00Z TAF Period

VFR conditions will prevail across all terminals during the duration
of this TAF Period. It will be very windy at the KGTF, KCTB, and
KHVR terminals from now through about 16/18Z. From now through
16/14Z there will be wind gusts in excess of 55 kts at the KCTB
terminal and 45 kts at the KGTF terminal. There will be instances
of low-level wind shear and mountain wave turbulence during the
duration of this TAF Period across North-central, Central, and
Southwestern Montana. -IG

&&

.HYDROLOGY...

Mild daytime and overnight temperatures will lead to rapid melting
of the recent snow across eastern portions of north-central MT. With
initially frozen ground, much of the snowmelt is likely to remain
on the surface and may lead to standing water. While overall
impact to creek/stream levels is low, most creeks are likely to be
frozen with potential for water flow over the ice or potentially
back up in some creek bottoms. Hoenisch

&&

.PRELIMINARY POINT TEMPS/POPS...
GTF  47  52  40  50 /  10  10  20  60
CTB  39  45  33  45 /  30  10  40  50
HLN  42  52  36  48 /  30  20  30  90
BZN  40  55  36  51 /  10  20  10  90
WYS  26  40  30  39 /  20  30  50 100
DLN  40  54  36  47 /  10  10  10  90
HVR  35  44  30  43 /  10  20  30  50
LWT  40  46  34  48 /  20  10  10  60

&&

.TFX WATCHES/WARNINGS/ADVISORIES...
High Wind Warning until 11 AM MST Tuesday for Bears Paw
Mountains and Southern Blaine-Cascade County below 5000ft-
Eastern Pondera and Eastern Teton-Fergus County below 4500ft-
Hill County-Judith Basin County and Judith Gap-Little Belt and
Highwood Mountains-Madison River Valley-Northern Blaine County-
Snowy and Judith Mountains-Upper Blackfoot and MacDonald Pass-
Western and Central Chouteau County.

High Wind Warning from 3 AM Wednesday to midnight MST Wednesday
night for Bears Paw Mountains and Southern Blaine-Beaverhead and
Western Madison below 6000ft-Big Belt, Bridger and Castle
Mountains-Canyon Ferry Area-Cascade County below 5000ft-East
Glacier Park Region-Eastern Glacier, Western Toole, and Central
Pondera-Eastern Pondera and Eastern Teton-Eastern Toole and
Liberty-Elkhorn and Boulder Mountains-Fergus County below 4500ft-
Gallatin Valley-Gallatin and Madison County Mountains and
Centennial Mountains-Gates of the Mountains-Helena Valley-Hill
County-Judith Basin County and Judith Gap-Little Belt and
Highwood Mountains-Madison River Valley-Meagher County Valleys-
Missouri Headwaters-Northern Blaine County-Northern High Plains-
Northwest Beaverhead County-Ruby Mountains and Southern
Beaverhead Mountains-Snowy and Judith Mountains-Southern High
Plains-Southern Rocky Mountain Front-Upper Blackfoot and
MacDonald Pass-Western and Central Chouteau County.

Winter Storm Watch from Tuesday evening through Wednesday
evening for East Glacier Park Region-Southern Rocky Mountain
Front.

High Wind Warning until 8 AM MST Tuesday for East Glacier Park
Region-Eastern Glacier, Western Toole, and Central Pondera-
Eastern Toole and Liberty-Northern High Plains-Southern High
Plains-Southern Rocky Mountain Front.

&&

http://www.weather.gov/greatfalls

Preliminary Local Storm Report
National Weather Service Great Falls MT
1142 PM MST Mon Dec 15 2025

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1127 PM     Non-Tstm Wnd Gst 15 E Whitlash           48.91N 110.91W
12/15/2025  M67 MPH          Liberty            MT   Mesonet

            Mesonet station GW0718 Joplin 25nnw.

&&

IG

Preliminary Local Storm Report
National Weather Service Great Falls MT
1154 PM MST Mon Dec 15 2025

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1147 PM     Non-Tstm Wnd Gst 15 E Whitlash           48.91N 110.91W
12/15/2025  M69 MPH          Liberty            MT   Mesonet

            Mesonet station GW0718 Joplin 25nnw.

&&

IG

Preliminary Local Storm Report
National Weather Service Great Falls MT
1155 PM MST Mon Dec 15 2025

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0821 AM     Non-Tstm Wnd Gst 8 SE East Glacier Park  48.36N 113.11W
12/15/2025  M73 MPH          Glacier            MT   Mesonet

            Mesonet station DCRM8 Deep Creek RAWS.

1045 PM     Non-Tstm Wnd Gst 4 ESE Chinook           48.58N 109.16W
12/15/2025  M63 MPH          Blaine             MT   Mesonet

            Mesonet station MTM48 Chinook E - MDA.

1030 PM     Non-Tstm Wnd Gst 1 NW Chinook            48.60N 109.24W
12/15/2025  M62 MPH          Blaine             MT   Mesonet

            Mesonet station MTCHK Chinook Us-2 Mp 403.5.

1140 PM     Non-Tstm Wnd Gst 20 E Whitlash           48.94N 110.82W
12/15/2025  M58 MPH          Liberty            MT   Mesonet

            Mesonet station GW0637 Bears Den 9 Ene.

&&

Preliminary Local Storm Report
National Weather Service Great Falls MT
1156 PM MST Mon Dec 15 2025

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0300 PM     Non-Tstm Wnd Gst 1 WSW Sun Prairie       47.53N 111.50W
12/15/2025  M55 MPH          Cascade            MT   Mesonet

            Mesonet station FW5493 Vaughn.

&&

Preliminary Local Storm Report
National Weather Service Great Falls MT
1157 PM MST Mon Dec 15 2025

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0715 PM     Non-Tstm Wnd Gst 6 WNW Ledger            48.29N 111.94W
12/15/2025  M56 MPH          Pondera            MT   Mesonet

            Mesonet station MTVAR Valier Jct 1-15 Mp
            347.0.

1027 PM     Non-Tstm Wnd Gst 3 WNW Raynesford        47.28N 110.80W
12/15/2025  M55 MPH          Cascade            MT   AWOS

            AWOS station K1AM Alpha.

&&

Preliminary Local Storm Report
National Weather Service Great Falls MT
1240 AM MST Tue Dec 16 2025

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

1146 PM     Non-Tstm Wnd Gst 1 E Roy                 47.33N 108.93W
12/15/2025  M61 MPH          Fergus             MT   AWOS

            AWOS station K1OM Oscar.

1218 AM     Non-Tstm Wnd Gst 13 S Fort Belknap       48.30N 108.72W
12/16/2025  M60 MPH          Blaine             MT   Mesonet

            Mesonet station FBLM8 Fort Belknap RAWS.

1057 PM     Non-Tstm Wnd Gst 5 NNE Forestgrove       47.06N 109.03W
12/15/2025  M58 MPH          Fergus             MT   AWOS

            AWOS station K1NM 5 NE Forestgrove.

1113 PM     Non-Tstm Wnd Gst 3 WNW Raynesford        47.28N 110.80W
12/15/2025  M58 MPH          Cascade            MT   AWOS

            AWOS station K1AM Alpha.

1207 AM     Non-Tstm Wnd Gst 4 WSW Great Falls       47.48N 111.38W
12/16/2025  M58 MPH          Cascade            MT   Official NWS Obs

            58 mph gust at Great Falls International
            Airport ASOS.

1225 AM     Non-Tstm Wnd Gst 8 SSW Fort Benton       47.72N 110.70W
12/16/2025  M58 MPH          Chouteau           MT   Mesonet

            Mesonet station DVI01740 Fort Benton.

&&