An arctic air mass pushed southward in western Montana Sunday night into Monday(Nov. 10). There was a period of rain on Sunday before the arctic air mass moved through setting up the stage for a flash freeze and snow combination by Sunday night. After the arctic cold front passed south through the Missoula Valley around midnight and entered the Bitterroot Valley, a period of heavy snow developed from Missoula south to Lolo and east to Clinton. Most roads were either snow-covered, or ice and snow-covered, which hampered travel during the Monday morning commute. These impacts were especially severe given near-record high temperatures earlier in the week.

Winter Storm in WEST GLACIER REGION, MONTANA
From 09-NOV-14 16:45:00 to 10-NOV-14 11:00:00 (MST-7)
Property damage: 3.00K
Reported by: Trained Spotter

A spotter estimated strong arctic winds gusting to 30 mph near Essex, MT. Glacier Park International Airport saw a peak gust of 48 mph when the arctic air began to spill into the Flathead Valley, and this wind likely topped 50 mph in the Bad Rock canyon region. Police dispatch reported wind knocking down multiple trees in West Glacier, MT. An additional hazard was rain, which fell before the arctic cold front. The flash-freezing of this water on roads contributed to very slick road conditions, as reported by spotters.

Winter Storm in FLATHEAD/MISSION VALLEYS, MONTANA
From 09-NOV-14 18:20:00 to 10-NOV-14 11:00:00 (MST-7)
Property damage: 15.00K
Reported by: ASOS

Glacier Park International Airport saw a peak gust of 48 mph when the arctic air began to spill into the Flathead Valley. At the airport, sustained 32 mph winds with gusts to 40 mph were commonplace, and visibility down to 0.75 mi was reported at times. These winds caused multiple trees falling across roadways in Whitefish and Kalispell. Power outages and ���treacherous��� road conditions impacted many and were reported by weather spotters. ASOS reports of rain before the cold winds explained why a weather spotter in Columbia Falls tweeted that there was a solid sheet of ice beneath the snow.

Winter Storm in BUTTE / BLACKFOOT REGION, MONTANA
From 09-NOV-14 19:20:00 to 10-NOV-14 11:00:00 (MST-7)
Property damage: 8.00K
Reported by: Department of Highways

The Butte DOT reported being extremely busy, with semi trucks stuck on Homestake Pass being a major impact for them. ASOS wind gusts at Butte's airport measured as high as 52mph. Farther north, a trained spotter reported 5 of snow in Deer Lodge, MT.

Winter Storm in POTOMAC / SEELEY LAKE REGION, MONTANA
From 09-NOV-14 21:00:00 to 10-NOV-14 11:00:00 (MST-7)
Property damage: 10.00K
Reported by: Department of Highways

Accidents, slick roads, and whiteout conditions reported along I-90 by DOT partners and county sheriffs. The Kraft Creek SNOTEL at 4750 ft reported 7��� of snow.

Winter Storm in MISSOULA / BITTERROOT VALLEYS, MONTANA
From 10-NOV-14 00:00:00 to 10-NOV-14 11:00:00 (MST-7)
Property damage: 60.00K
Reported by: Department of Highways

The MDT reported that the quick transition from warm to cold with the quick freezing of rain under snow presented crews with a difficult challenge in keeping roads navigable, and they had over 30 weather-related accidents. Slick roads and whiteout conditions reported by county sheriffs. Icy roads caused a very slow commute for NWS employees and workers across Missoula.