During the 7th through 9th, North-Central and Southwest Montana resided underneath northwesterly flow aloft associated with the polar front jet stream. In addition, multiple disturbances embedded within this flow interacted with a frontal boundary that wavered over the area from southwest to northeast and vice versa. The resulting lift, combined with abundant moisture in the low- to mid-level atmosphere, contributed to the formation of periods of snow over North-Central and Southwest Montana. In addition, it is believed mesoscale bands of heavy snow that affected portions of North-Central Montana on the 8th into early morning of the 9th were tied to frontogenesis in the 850 mb to 700 mb layer.

Winter Storm in BLAINE, MONTANA
From 08-FEB-18 06:40:00 to 08-FEB-18 06:40:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

Montana DOT reported severe driving conditions along MT-66 from the junction with US-191 to Hays.

Winter Storm in FERGUS, MONTANA
From 08-FEB-18 06:40:00 to 08-FEB-18 06:40:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

Montana DOT reported severe driving conditions on US-191 from 5-miles south of the Fred Robinson Bridge to the junction with MT-66.

Winter Storm in HILL, MONTANA
From 08-FEB-18 10:55:00 to 08-FEB-18 10:55:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Spotter reported the combination of moderate snow and blowing snow was producing near-zero visibility in Havre. Snow drifts up to 3 feet deep caused several cars to become stuck.

Winter Storm in EASTERN TETON, MONTANA
From 09-FEB-18 09:00:00 to 09-FEB-18 09:00:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Spotter in Fairfield reported 9-inches of new snow in 24-hours.

Winter Storm in SOUTHERN LEWIS AND CLARK, MONTANA
From 08-FEB-18 11:36:00 to 08-FEB-18 11:36:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Broadcast media reported early dismissal for Helena Public Schools on Feb 8th due to winter weather. In addition, Helena Public Schools were closed on Feb 9th for the same reason.

Winter Storm in JUDITH BASIN, MONTANA
From 08-FEB-18 12:48:00 to 08-FEB-18 12:48:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

US-191 closed from Eddie's Corner to junction with US-12 just east of Harlowton.

Winter Storm in NORTH ROCKY MOUNTAIN FRONT, MONTANA
From 08-FEB-18 14:06:00 to 08-FEB-18 14:06:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

Montana DOT reported severe driving conditions along MT-464 (i.e. Duck Lake Road) from Browning to 12 miles north of Browning.

Winter Storm in CHOUTEAU, MONTANA
From 08-FEB-18 19:25:00 to 08-FEB-18 19:25:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

Montana DOT reported severe driving conditions on US-87 from Loma to Big Sandy.

Winter Storm in SOUTHERN ROCKY MOUNTAIN FRONT, MONTANA
From 08-FEB-18 16:50:00 to 08-FEB-18 16:50:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Spotter located 16-miles WSW of Bynum reported 6-inches of new snow in 12-hours.

Winter Storm in CASCADE, MONTANA
From 08-FEB-18 21:45:00 to 08-FEB-18 21:45:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Employee

Estimated snowfall rates of 1.0 to 1.5-inches per hour at Great Falls WFO as heavy snow bands shifted southward over the Great Falls area. Visibility was reduced to near 1/4 mile.