A potent shortwave within a larger scale trough overspread the region late evening on the 26th into the 27th. This resulted in a cold front moving across the region, mostly during the morning of the 27th.
Every event with a place to put it; 5 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS TFX wrote it up.
A potent shortwave within a larger scale trough overspread the region late evening on the 26th into the 27th. This resulted in a cold front moving across the region, mostly during the morning of the 27th. Strong gusts and a few snow squalls accompanied this front as it progressed through the region.
Behind the cold front there were a few instances of extreme cold across the Hi-Line (Temperatures or wind chills of -35F or less).
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Great Falls, MT wrote its last area forecast discussion before the first event at Dec 27, 8:11 AM MST, 1 hour 6 minutes earlier. Its key messages:
Area Forecast Discussion National Weather Service Great Falls MT 811 AM MST Sat Dec 27 2025 .KEY MESSAGES... - An Arctic front will move southward through the area today. - Strong and gusty north winds will accompany and follow the Arctic front, with temperatures falling rapidly in its wake. - Accumulating snow, heaviest in the mountains, will occur through the daylight hours today before dissipating this evening from north to south. - This cold snap will be short-lived, with temperatures starting to warm back up on Sunday. && .UPDATE... The Pacific cold front has largely exited the region this morning, just hanging on across portions of Southwest Montana. Snow has been a bit more persistent along and behind this front, especially in the Gallatin Valley. Given the favorable wind direction behind the front for lingering snow in the Gallatin Valley (West to northwest), we opted to issue a Winter Weather Advisory through 11 AM. Additional snow amounts up to two inches or so are forecast over this timeframe, particularly for areas on the southeast side of the Gallatin Valley, including Bozeman. Snow gradually diminishes late morning into early afternoon. No changes were made elsewhere this morning. Significantly colder temperatures continue to stream in from the north behind the Canadian cold front. Temperatures across most areas will struggle to rise much, if any today. Ongoing Cold Weather Advisories and Extreme Cold Warnings are in good shape, with no changes made to those at this time. -AM && .DISCUSSION... /Issued 425 AM MST Sat Dec 27 2025/ Longwave trough and attendant Pacific cold front were moving east and over the Northern Rockies early this morning, with a surface low emerging over the plains of North Central Montana and an Arctic front pushing south from Alberta. As the morning progresses the longwave trough axis and Pacific cold front will pivot east and over Southwest through North Central Montana through 18-21z all the while the aforementioned Arctic front surges south through North Central, Central, and Southwest Montana through 07-11z, 11-16z, and 16-23z respectively. A period (2-4 hours) of moderate to heavy snow will accompany the passage of the longwave trough and Pacific front; with additional light to at times moderate snow occurring along and after the Arctic front, especially in the northerly upslope regions of Central and Southwest Montana, through the late afternoon today/early evening hours tonight. Surface high pressure rapidly building south along the Canadian Rockies will help to drive pressure rises in excess of 10mb per 6hr over much of North Central through Southwest Montana in wake of the Arctic front, which will result in a 6-12hr period of strong and gusty north winds. These northerly winds will be especially strong in lee of the Island Ranges and in terrain gaps, with the potential for surface wind gusts to approach 50kts in these locations. Temperatures will fall rapidly in wake of the Arctic front, with most of the plains of North Central and Central Montana seeing their high temperatures occur prior to sunrise today. The aforementioned strong north winds combined with temperatures plunging into the single digits above/below zero across the plains and Island Ranges of Central and North Central Montana will help to support wind chill values ranging from -25 to nearly -40 degrees through the late evening hours tonight or morning hours on Sunday. For this reason Cold Weather Advisory's and Extreme Cold Warnings remain in place. Further south across Southwest and the remainder of Central Montana (i.e. south of the Island Ranges) temperatures will be slower to cool thanks to the cold air interacting with the terrain of Central Montana, but wind chills as low as -10 to -20 degrees will still occur. The prior mentioned surface high will continue to build south into Montana through the overnight hours tonight as the longwave trough digs towards the Upper Mississippi River Valley and ridging builds into the Pacific Northwest. This surface high and the upper level ridge building in over the Pacific Northwest will lead to clearing skies across the Northern Rockies and relaxing surface winds, which will support ideal conditions for radiational cooling through the night tonight. Low temperatures across Southwest through North Central Montana will fall to near zero to the teens below zero, with the coldest temperatures occurring near the international border and in cold prone areas that see appreciable snow over the next 12-18 hours. The remainder of the forecast period see upper level ridging slowly building east and over the Northern Rockies, with temperatures moderating through the remainder of the weekend and early next week. - Moldan && .AVIATION... 27/12Z TAF Period A series of cold fronts will moves across the Northern Rockies through the day today, with initially gusty west winds pivoting to the north. Temperatures will fall rapidly in wake of the northward wind shift, with gusty conditions persisting some 6-12 hours after this shift. In addition to the winds a period of snow will accompany each front, with reductions in VIS to generally IFR/MVFR. Low CIGS of VLIFR/LIFR/IFR will occur over the plains of Central and North Central Montana in wake of the northward wind shift and persist through the afternoon hours before gradually improving. Mountain obscuration will occur through 03-09z Sunday. - Moldan && .PRELIMINARY POINT TEMPS/POPS... GTF 9 -5 24 18 / 50 10 0 0 CTB 0 -13 21 16 / 40 10 0 0 HLN 30 -1 22 11 / 60 20 0 0 BZN 29 0 21 4 / 80 20 0 0 WYS 30 -13 16 -5 / 90 30 0 0 DLN 27 2 22 6 / 50 10 0 0 HVR 9 -14 5 0 / 80 20 0 0 LWT 20 -6 20 10 / 50 10 0 0 && .TFX WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory until 2 PM MST this afternoon for Big Belt, Bridger and Castle Mountains-East Glacier Park Region- Gallatin and Madison County Mountains and Centennial Mountains- Little Belt and Highwood Mountains-Northwest Beaverhead County- Southern Rocky Mountain Front-Upper Blackfoot and MacDonald Pass. Cold Weather Advisory until 5 AM MST Sunday for East Glacier Park Region-Northern High Plains. Extreme Cold Warning until 5 AM MST Sunday for Eastern Glacier, Western Toole, and Central Pondera-Eastern Toole and Liberty. Cold Weather Advisory until 10 PM MST this evening for Cascade County below 5000ft-Eastern Pondera and Eastern Teton-Judith Basin County and Judith Gap-Little Belt and Highwood Mountains- Southern High Plains-Southern Rocky Mountain Front-Western and Central Chouteau County. Extreme Cold Warning until 11 AM MST Sunday for Bears Paw Mountains and Southern Blaine-Hill County-Northern Blaine County. Cold Weather Advisory until 11 AM MST Sunday for Fergus County below 4500ft-Snowy and Judith Mountains. Winter Weather Advisory until 11 AM MST this morning for Gallatin Valley. && http://www.weather.gov/greatfalls
Special Weather Statement National Weather Service Great Falls MT 541 AM MST Sat Dec 27 2025 MTZ305-306-311-313-314-318-321-323>326-328-329-271400- Hill County-Northern Blaine County- Bears Paw Mountains and Southern Blaine- Judith Basin County and Judith Gap-Fergus County below 4500ft- Snowy and Judith Mountains-Meagher County Valleys- Canyon Ferry Area-Missouri Headwaters-Madison River Valley- Gallatin Valley-Beaverhead and Western Madison below 6000ft- Ruby Mountains and Southern Beaverhead Mountains- Including the cities of Havre, Chinook, Zurich, Harlem, Hogeland, Fort Belknap, Rocky Boy, Raynesford, Geyser, Stanford, Windham, Benchland, Hobson, Moccasin, Hilger, Lewistown, Martinsdale, Checkerboard, Ringling, White Sulphur Springs, Toston, Townsend, Winston, Harrison, Three Forks, Willow Creek, Pony, Whitehall, Cameron, Ennis, Jeffers, McAllister, Norris, Bozeman, Gallatin Gateway, Bannack, Dillon, Glen, Waterloo, and Monida Pass 541 AM MST Sat Dec 27 2025 ...Gusty Winds and Reduced Visibility... A Pacific cold front was moving east early this morning, with a band of moderate to at times heavy snow accompany the front. While snowfall accumulations are likely to remain below one inch through sunrise this morning a period of reduced visibility, with visibilities falling to as low as one mile, is likely to occur. In addition to the reduced visibility a period of strong and gusty winds of between 45 to 55 mph will occur. Travelers should be prepared for changing conditions and allow extra time to reach your destination. Moldan
Preliminary Local Storm Report
National Weather Service Great Falls MT
544 AM MST Sat Dec 27 2025
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0530 AM Non-Tstm Wnd Gst 2 E Inverness 48.55N 110.65W
12/27/2025 M56 MPH Hill MT Mesonet
Mesonet station MTINV Inverness (MT DOT).
&&
MoldanPreliminary Local Storm Report
National Weather Service Great Falls MT
545 AM MST Sat Dec 27 2025
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0415 AM High Sust Winds 4 NNE Mcallister 45.50N 111.70W
12/27/2025 M39 MPH Madison MT Mesonet
Average sustained wind speed of 39 mph from
0315 to 0415 local time.
&&
MoldanSpecial Weather Statement National Weather Service Great Falls MT 707 AM MST Sat Dec 27 2025 MTZ325-326-271615- Madison River Valley-Gallatin Valley- Including the cities of Cameron, Ennis, Jeffers, McAllister, Norris, Bozeman, and Gallatin Gateway 707 AM MST Sat Dec 27 2025 ... Additional Mainly Light Snow This Morning... A cold front continues to make slow progress across Southwest Montana this morning. Bands of snow lingering along and behind this front will result in additional snow to around an inch or so at lower elevations through mid-morning. If driving this morning, be prepared for reduced visibility and winter driving conditions.
Preliminary Local Storm Report
National Weather Service Great Falls MT
720 AM MST Sat Dec 27 2025
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0520 AM Non-Tstm Wnd Gst 11 SSE Whitlash 48.75N 111.17W
12/27/2025 M59 MPH Liberty MT Mesonet
Mesonet station GW2412 Hill 2sw.
&&
AMPreliminary Local Storm Report
National Weather Service Great Falls MT
917 AM MST Sat Dec 27 2025
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0917 AM Snow 5 ESE Bozeman Hot Sprin 45.61N 111.10W
12/27/2025 M4.0 Inch Gallatin MT Trained Spotter
4 inches of snow since 5:30am.
&&
MPLThe national radar mosaic for the moment the first event began.
3 winter weather, 2 extreme cold/wind chill. Local standard time, as filed.
Mesonet station GW5555 Grassy Butte 3SE measured a -36F wind chill.
Snow Squall. AWOS station K1FM Foxtrot measured a quick reduction in visibility to one-eighth of a mile.
Snow Squall. MDT station Spokane Creek camera showed a rapid reduction in visibility with a quick coating of snow on US 12/287.
FAA cameras at the Townsend Airport showed a quick reduction in visibility down to approximately 1,400ft from snow.
Montana mesonet station Hogeland SW measured a -39F wind chill.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Montana in 2025Every state in 2025This day in weather historyWarnings in Montana, December 2025
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 1306758, 1306694, 1306695, 1306696, 1306757.