A winter storm and associated arctic front brought widespread snowfall and travel impacts to much of western Montana. Hardest hit areas were forecast to be from roughly I-90 and points north and west. The Missoula and Bitterroot valleys and most locations across SW MT were not hit as hard as forecast until midday Sunday, 12/28, when a convergence band set up and dropped 4 to 7 inches in Missoula, with 4 inches measured at the Missoula National Weather Service Forecast Office for the day. The accident rate was very high in the Missoula area, with 8-12 slideoffs/hour being reported from 2pm until 5pm. Impacts for Missoula lessened after 5pm on 12/28, but Butte continued to see moderate snow throughout the evening.

Winter Storm in FLATHEAD/MISSION VALLEYS, MONTANA
From 27-DEC-14 17:00:00 to 28-DEC-14 08:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

As snow began to fall over the Flathead Valley, reports of crashes and slide offs began to increase sharply around 5 pm on the 27th. By the next morning, a storm spotter in Colombia Falls reported 13.5 inches of snow during this event. Over the Mission Valley, storm spotters reported 13 inches of storm total snow in Polson and 9 inches in Ronan. Strong winds associated with the arctic cold front caused numerous power outages over the Flathead Valley. Sustained winds of 43 mph over Flathead Lake near Yellow Bay was recorded by mesonet sensors for several hours.

Winter Storm in POTOMAC / SEELEY LAKE REGION, MONTANA
From 27-DEC-14 18:00:00 to 28-DEC-14 18:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Newspaper

A moist weather system brought heavy snow and dangerous back country conditions to the Seeley Lake region. Local media reported 4 snowmobilers were buried in an avalanche in the North Fork Bowl area, but were able to ride out on their own. 8 inches of snow was measured by a SNOTEL 6 hours before the avalanche.  A spotter from Condon also reported 14 inches of snow over 24 hours.

Heavy Snow in LOWER CLARK FORK REGION, MONTANA
From 27-DEC-14 17:00:00 to 28-DEC-14 06:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Lookout Pass ski resort reported 17 inches of snow over a 24 hour period. Out of the 17 inches, 14 inches of snow fell between 4 pm MST Saturday and 5 am MST Sunday. MDT required that towing vehicles use chains after 5 pm on the 27th.

Winter Storm in LOWER CLARK FORK REGION, MONTANA
From 28-DEC-14 17:00:00 to 28-DEC-14 19:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

As the arctic front continued to move through western Montana, a snow band developed near Missoula and eventually made its way over Interstate 90 between Frenchtown and Superior. Multiple accidents and slide offs were reported with whiteout conditions under the heavy snow band.

Winter Storm in WEST GLACIER REGION, MONTANA
From 27-DEC-14 12:00:00 to 28-DEC-14 18:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A storm spotter reported 13 inches of snow in Essex over 48 hours with periods of blowing and drifting snow when the arctic air moved through. Also, the MDT reported periods of moderate to heavy snow during this event along US-2 and also mentioned that there were times when they had a difficult time keeping up with the snowfall.

Winter Storm in KOOTENAI/CABINET REGION, MONTANA
From 27-DEC-14 17:00:00 to 28-DEC-14 11:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A storm spotter from Olney reported 12 inches of snow over 24 hours with periods of 1/4 mile visibility at times during this holiday weekend.  Another spotter from Marion reported around 8 inches of snow on the 28th.

Winter Storm in BITTERROOT / SAPPHIRE MOUNTAINS, MONTANA
From 27-DEC-14 18:00:00 to 28-DEC-14 06:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

Lost Trail Pass received 14 inches of snow and 10 inches of snow fell at Lolo pass over a 24 hour period. Periods of blowing and drifting snow also occurred at Lost Trail pass.

Winter Storm in MISSOULA / BITTERROOT VALLEYS, MONTANA
From 28-DEC-14 14:00:00 to 28-DEC-14 17:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

A heavy snow band developed along the arctic frontal boundary and caused numerous accidents between Frenchtown and the west end of Missoula valley. This resulted to the shutdown of the westbound lanes on Interstate 90 for a couple of hours. An observation of 3.3 inches of snow was reported at the Missoula International Airport from this band which lasted around 2 hours.