Montana, 2022

Winter Storm and Extreme Cold in Montana, December 20 to 22, 2022

December 20 to 22, 2022 · NWS MSO · 15 events in 8 counties and zones

A strong upper level jet and Pacific moisture combined with arctic air stalled over northwest Montana, led to multiple hours of heavy snow rates and difficult travel. Strong arctic winds brought wind chills down to 70 below zero along the Divide and dangerous wind chills across western Montana.

Where it happened

Every event with a place to put it; 15 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.

  • Tornadoes
  • Tropical storms and surge
  • Floods
  • Wind
  • Hail
  • Winter weather
  • Heat and drought
  • Cold
  • Fire, smoke and dust
  • Marine and coastal
  • Other

Open the live radar over this ground

The toll

Deaths
0
Injuries
0
Property damage
None recorded
Crop damage
None recorded
Events
15

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.

What happened

The episode as NWS MSO wrote it up.

A strong upper level jet and Pacific moisture combined with arctic air stalled over northwest Montana, led to multiple hours of heavy snow rates and difficult travel. Strong arctic winds brought wind chills down to 70 below zero along the Divide and dangerous wind chills across western Montana. A flash freeze and blowing snow were observed across west-central Montana when the arctic cold front pushed through overnight. As skies cleared, extreme cold to 50 below zero were observed along the Divide.

What forecasters said that day

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 Missoula, MT wrote its last area forecast discussion before the first event at Dec 20, 3:55 AM MST, 4 hours 5 minutes earlier.

Area forecast discussion, Dec 20, 3:55 AM MST, 4 hours 5 minutes before
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The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

8 extreme cold/wind chill, 7 winter storm. Local standard time, as filed.

Winter Storm, Kootenai/Cabinet Region

When
December 20, 8:00 AM MST to 9:00 PM MST
Where
Kootenai/Cabinet Region forecast zone
Reported by
Department of Highways
Coordinates
48.171, -114.863 (the zone’s center; the record gives no point)

MDT reported snowfall rates in excess of 1 inch per hour in Libby for 9 consecutive hours. Trained spotters in Libby reported 14 inches of snow. Snow, blowing and drifting snow led to whiteout conditions on US Highway 2 and 93.

Winter Storm, Lower Clark Fork Region

When
December 20, 11:00 AM MST to December 21, 1:00 AM MST
Where
Lower Clark Fork Region forecast zone
Reported by
Department of Highways
Coordinates
47.286, -114.685 (the zone’s center; the record gives no point)

MDT declared severe driving conditions on Interstate 90 from Tarkio to Lookout Pass as snowfall rates up to 2 inches per hour were observed. Wind gusts of 30 to 35 mph led to areas of blowing and drifting snow in the mountains. Between 8 to 14 inches of snow fell along the Highway 200 corridor, which led to cancellations of area schools on December 22.

Winter Storm, West Glacier Region

When
December 20, 11:00 AM MST to December 21, 8:00 AM MST
Where
West Glacier Region forecast zone
Reported by
COOP Observer
Coordinates
47.971, -114.069 (the zone’s center; the record gives no point)

Heavy snow and east-northeast winds of 20-30 mph with gusts to 45 mph led to periods of whiteout conditions on US Highway 2 east of West Glacier. MDT and the Essex COOP reported 29 inches of snowfall. 14 inches of snow was measured in West Glacier.

Winter Storm, Flathead/Mission Valleys

When
December 20, 11:00 AM MST to December 21, 11:00 AM MST
Where
Flathead/Mission Valleys forecast zone
Reported by
Law Enforcement
Coordinates
47.872, -114.424 (the zone’s center; the record gives no point)

Widespread heavy snowfall, with rates up 2 inches per hour, was observed on December 20th. Snowfall accumulations of 5 to 12 inches was reported, with Bigfork receiving 14 inches. Arctic north-northeast winds of 30 to 50 mph led to widespread blowing and drifting snow on December 21st. Lake County officials declared emergency travel as area roadways became impassable. Flathead County closed Hodgson Road due to drifting snow. Numerous schools announced closures on December 21st.

Winter Storm, Bitterroot / Sapphire Mountains

When
December 20, 2:00 PM MST to December 21, 8:00 AM MST
Where
Bitterroot / Sapphire Mountains forecast zone
Reported by
Department of Highways
Coordinates
46.508, -113.828 (the zone’s center; the record gives no point)

MDT reported a flash freeze, blowing and drifting snow, as the arctic front arrived on December 21st. 12 inches of snow was reported at Lost Trail Pass, with at least 13 inches accumulating at Lolo Pass.

Winter Storm, Butte / Blackfoot Region

When
December 20, 11:50 PM MST to December 21, 11:00 AM MST
Where
Butte / Blackfoot Region forecast zone
Reported by
Department of Highways
Coordinates
46.306, -113.025 (the zone’s center; the record gives no point)

Snow, blowing and drifting snow, and dangerous wind chills impacted areas along US Highway 12 and Interstate 90, prompting MDT to declare severe driving conditions. Numerous slide offs occurred between Garrison Junction and Deer Lodge, where visibility below one quarter of a mile was observed by area spotters and mesonets. Wind chills dropped between 30 and 50 below as north-northeast winds reached 20 to 30 mph and temperatures dropped in the teens to low 20s below zero. MacDonald Pass reported a wind chill of 60 below zero.

Winter Storm, Missoula / Bitterroot Valleys

When
December 21, 1:00 AM MST to 11:00 AM MST
Where
Missoula / Bitterroot Valleys forecast zone
Reported by
Department of Highways
Coordinates
46.560, -114.023 (the zone’s center; the record gives no point)

Roadways experienced a flash freeze, and blowing and drifting snow as the arctic front arrived, which led to MDT declaring severe driving conditions. Numerous schools closed due to weather on December 21st.

Extreme Cold/Wind Chill, West Glacier Region

When
December 21, 8:00 AM MST to December 22, 11:14 AM MST
Where
West Glacier Region forecast zone
Reported by
Mesonet
Coordinates
47.971, -114.069 (the zone’s center; the record gives no point)

Widespread wind chills of 40 to 55 below zero were observed. Snowslip Mountain in Glacier National Park recorded a wind chill of 70 below zero. Temperatures fell to 49 below at Marias Pass, 47 below in Polebridge, 36 below in Hungry Horse, and 34 below in West Glacier.

Extreme Cold/Wind Chill, Flathead/Mission Valleys

When
December 21, 11:00 AM MST to December 22, 11:00 AM MST
Where
Flathead/Mission Valleys forecast zone
Reported by
Mesonet
Coordinates
47.872, -114.424 (the zone’s center; the record gives no point)

Wind chills dropped to 30 to 40 below zero across the Flathead Valley and to 30 below in the Mission Valley on the December 21st. Temperatures dropped to 34 below in Kalispell (7th coldest on record) and Hot Springs. Creston dropped to 35 below zero. Several thousand people lost power during the morning of December 21st across the Flathead Valley.

Extreme Cold/Wind Chill, Butte / Blackfoot Region

When
December 21, 11:00 AM MST to December 22, 9:30 AM MST
Where
Butte / Blackfoot Region forecast zone
Reported by
Mesonet
Coordinates
46.306, -113.025 (the zone’s center; the record gives no point)

Temperatures fell between 35 and 43 below zero. Butte dropped to 40 below zero. Discovery Ski Area closed due to extreme cold.

Extreme Cold/Wind Chill, Potomac / Seeley Lake Region

When
December 21, 5:30 PM MST to December 22, 10:15 AM MST
Where
Potomac / Seeley Lake Region forecast zone
Reported by
COOP Observer
Coordinates
46.986, -113.597 (the zone’s center; the record gives no point)

Low temperatures on December 22nd reached 49 below in Potomac, and 41 below in Seeley Lake and in Clearwater Junction. Extreme cold closed Snowbowl Ski Area.

Extreme Cold/Wind Chill, Kootenai/Cabinet Region

When
December 21, 8:00 PM MST to December 22, 11:00 AM MST
Where
Kootenai/Cabinet Region forecast zone
Reported by
COOP Observer
Coordinates
48.171, -114.863 (the zone’s center; the record gives no point)

Temperatures fell between 20 and 41 below. Notable observations include: 41 below Olney, 39 below Yaak, and 31 below in Libby.

Extreme Cold/Wind Chill, Bitterroot / Sapphire Mountains

When
December 21, 8:00 PM MST to December 22, 1:00 PM MST
Where
Bitterroot / Sapphire Mountains forecast zone
Reported by
Public
Coordinates
46.508, -113.828 (the zone’s center; the record gives no point)

Lost Trail Ski Area closed on December 22 as wind chills dropped to 47 below zero. Widespread wind chills of 40 below or colder were observed across mountain sites. Temperatures dropped between 20 and 30 below, with the Skalkaho summit Snotel hitting 34 below.

Extreme Cold/Wind Chill, Missoula / Bitterroot Valleys

When
December 21, 9:25 PM MST to December 22, 1:40 PM MST
Where
Missoula / Bitterroot Valleys forecast zone
Reported by
Mesonet
Coordinates
46.560, -114.023 (the zone’s center; the record gives no point)

Wind chills fell to 38 below zero in Missoula as sustained east winds of 15 to 25 mph were observed. Notable low temperatures include: 27 below Frenchtown, 26 below Stevensville, 24 below Hamilton, and 19 below Missoula.

Extreme Cold/Wind Chill, Lower Clark Fork Region

When
December 22, 6:00 AM MST to 12:00 PM MST
Where
Lower Clark Fork Region forecast zone
Reported by
Mesonet
Coordinates
47.286, -114.685 (the zone’s center; the record gives no point)

Wind chills reached 31 below in Thompson Falls and as low as 41 below in the mountains (Mullan Pass). Temperatures fell between 15 and 27 below.

What these are

Winter Storm
A storm that brought snow, sleet or freezing rain at warning levels, usually over several hours or days.
Extreme Cold/Wind Chill
Temperatures or wind chills at or below the local warning criteria, or cold that caused deaths.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

More

Every storm in Montana in 2022Every state in 2022This day in weather historyWarnings in Montana, December 2022

Sources

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 2026-09-30. Each event’s entry at NCEI: 1063134, 1063133, 1063135, 1063136, 1063140, 1063150, 1063138, 1063131, 1063137, 1063151, 1063149, 1063130, 1063141, 1063139, 1063132.