Moist warm air moving over the Northern Rockies brought heavy snow and freezing rain to parts of western Montana. Valley locations saw periods of moderate to heavy snow as residual arctic air kept temperatures cool, especially in northwest Montana. One inch per hour snowfall rates were common, with some valleys receiving over a foot of new snow during a 24-hour period.

Winter Storm in WEST GLACIER REGION, MONTANA
From 03-FEB-17 13:00:00 to 04-FEB-17 06:00:00 (MST-7)
Reported by: Department of Highways

The Montana Department of Transportation reported Severe Driving Conditions with blowing and drifting throughout the afternoon and evening of Feb. 3, lasting through the early morning of Feb. 4. They use this label sparingly, only when road conditions are treacherous. Road conditions improved by 7 am MST on Feb. 4. Glacier National Park officials estimated 8 inches of snow in West Glacier, MT between noon and 8 pm on Feb. 3rd, which translates to 1 inch or greater per hour snowfall rates.

Winter Storm in LOWER CLARK FORK REGION, MONTANA
From 03-FEB-17 15:30:00 to 04-FEB-17 18:00:00 (MST-7)
Property damage: 50.00K
Reported by: Department of Highways

Severe driving conditions were issued at 3:22 pm on Feb. 3 for a 33 mile stretch of I-90 leading up to Lookout Pass. Webcam images showed heavy snow throughout this time period. The Montana Department of Transportation reported at least two snow slides, one of which was at milepost 7, blocking individual lanes during the event. Highway patrol reported semi trucks stuck blocking lanes throughout the event, as well as semi truck accidents.

Winter Storm in MISSOULA / BITTERROOT VALLEYS, MONTANA
From 04-FEB-17 02:00:00 to 04-FEB-17 08:00:00 (MST-7)
Reported by: Department of Highways

Severe driving conditions were declared by the Montana Department of Transportation during the early morning hours of Feb. 4, due to snow-covered roads with blowing and drifting occurring. Freezing rain was also reported from Conner to Stevensville during the late evening of the 3rd.

Heavy Snow in FLATHEAD/MISSION VALLEYS, MONTANA
From 03-FEB-17 13:30:00 to 04-FEB-17 10:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter in Kalispell reported 14 inches of snow during this 21 hour time-frame. Public reports came in reporting the worst driving conditions between Creston and Columbia Falls they have experienced in 30 years. Plow drivers also reported 12 to 14 inches of new snow in Columbia Falls, MT.

Heavy Snow in KOOTENAI/CABINET REGION, MONTANA
From 03-FEB-17 13:00:00 to 04-FEB-17 16:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

A local emergency manager estimated 8 inches of snow in Libby, MT in 24 hours with this event. A public report agreed with this estimate, also stating 8 inches of snow had fallen during the same time-frame, with 15 inches snow depth on ground. Plow drivers stated they had a hard time keeping up with the snow rates. On February 8th, the governor of Montana declared a State of Emergency to help in providing resources for snow removal. The Eureka, MT AWOS sensor, located at the airport, reported multiple hours of heavy snow, with 0.25 mi or 0.50 mi visibility for much of the event.

Heavy Snow in BITTERROOT / SAPPHIRE MOUNTAINS, MONTANA
From 03-FEB-17 17:00:00 to 04-FEB-17 13:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Park/Forest Service

The public reported 15 inches of snow in 24 hours at Lolo Pass. Automated SNOTEL sensors suggested intense snowfall throughout the high terrain.