An arctic front passed through western Montana during a very busy holiday travel week, occurring on the days immediately preceding Thanksgiving. Strong winds, snow, blowing snow, and flash-freezing of roadways impacted most of the Northern Rockies. Dangerous travel conditions with hundreds of stranded vehicles and crashes lead to the Missoula County Sheriff to declare emergency-only travel due to ���extreme hazardous weather conditions���. Other valleys saw similar conditions with multiple inches of snow coupled with breezy winds.

Winter Storm in KOOTENAI/CABINET REGION, MONTANA
From 24-NOV-15 08:00:00 to 24-NOV-15 20:00:00 (MST-7)
Reported by: Trained Spotter

A trained spotter in Troy reported 4 inches during the morning hours. Another spotter reported 3.5 inches of snow north of Noxon, MT. Roads crews reported black ice on roads causing hazardous driving conditions.

Winter Storm in LOWER CLARK FORK REGION, MONTANA
From 24-NOV-15 04:30:00 to 25-NOV-15 03:00:00 (MST-7)
Property damage: 14.00K
Reported by: Department of Highways

Lookout Pass recorded 5 inches of snow during the event. A trained spotter reported a brief period of freezing drizzle before snow started. Seven slide-offs were recorded in the area throughout the day. Hwy 200 was especially bad during this storm, with several accidents and one semi truck getting stuck.

Winter Storm in BUTTE / BLACKFOOT REGION, MONTANA
From 24-NOV-15 11:00:00 to 25-NOV-15 08:00:00 (MST-7)
Property damage: 15.00K
Reported by: Law Enforcement

Heavy snow began falling during the late morning. Along I-90, a fatal accident occurred when a pickup truck lost control on the icy roads and went into a fence. Trained spotters reported between 5.3 to 3 inches from Anaconda to Butte.

Winter Storm in POTOMAC / SEELEY LAKE REGION, MONTANA
From 24-NOV-15 12:00:00 to 25-NOV-15 07:00:00 (MST-7)
Property damage: 4.00K
Reported by: Public

The public reported an estimated 6 inches of snow with this storm near Potomac. Highway 200 was snow-covered and slick, with multiple slide-offs. Area SNOTELs reported between 2 to 7 inches of snow, depending on location.

Winter Storm in MISSOULA / BITTERROOT VALLEYS, MONTANA
From 24-NOV-15 14:00:00 to 25-NOV-15 08:00:00 (MST-7)
Property damage: 80.00K
Reported by: Law Enforcement

There were widespread spotter reports of 3 to 4 inches of snow in Missoula during the afternoon and evening of 11/24. The highest report was 7.2 inches in the upper South Hills neighborhood of Missoula. The Missoula County Sheriff's office requested emergency travel only due to extreme hazardous weather conditions. This is their highest level of travel alert, and a significant impact to travel during the evening commute. The general travel ban lasted 3 hrs, and during this time, vehicles and buses were unable to drive up to houses in the hills around Missoula due to slick roads. Over 40 accidents and slide-offs occurred in Missoula & Bitterroot Valleys during this time frame. Many schools cancelled class the next day due to continued slick roads.

Winter Storm in WEST GLACIER REGION, MONTANA
From 24-NOV-15 07:30:00 to 25-NOV-15 00:00:00 (MST-7)
Reported by: Public

The public reported 4 inches of snow in Coram, and 3 inches in West Glacier. Winds gusting into the 30+ mph range cause blowing snow and low visibility at times.

Winter Storm in BITTERROOT / SAPPHIRE MOUNTAINS, MONTANA
From 24-NOV-15 14:00:00 to 25-NOV-15 08:00:00 (MST-7)
Reported by: SNOTEL

Nine inches of snow fell at Lolo Pass during the event, with snow-covered roads and slick driving conditions.

Winter Storm in FLATHEAD/MISSION VALLEYS, MONTANA
From 24-NOV-15 08:00:00 to 25-NOV-15 00:00:00 (MST-7)
Property damage: 120.00K
Reported by: Trained Spotter

Trained spotters reported between 3 to 5.8 inches of snow in Kalispell during the day, with drifts up to a foot and a half deep. Winds at the Glacier Park International Airport ASOS gusted to around 40 mph during the morning and afternoon, peaking at 41 mph in the late morning. Roads became very slick by the afternoon. Local law enforcement reported that snow and wind had caused over 60 vehicle accidents or slide-offs in the Flathead Valley.