A series of three weather systems moved through Montana between December 18 and 21, 2020, bringing strong winds with the first two systems on the 18-19th. Winds increased to 20-35 MPH with gusts to 40 MPH during the overnight hours on the 18-19. Winds would continue to increase a little through the morning, but weakening a bit in the afternoon.
Winds would pick up later in the evening on the evening of the 19th as the second system began to push into the area. This system would be the windiest of the three, with winds aloft at 700 mb increasing to 70kts/80MPH. These strong winds would mix down to the surface, resulting in wind gusts in excess of 70 and even 80 MPH. High Wind Warnings were issued across the area, especially across the North-Central Plains.
The third and final system would move into the area on Tuesday, which would go on to result in some mountain snow and gusty winds across the plains, but this will be recorded in a separate episode.

High Wind in BLAINE, MONTANA
From 20-DEC-20 10:18:00 to 20-DEC-20 10:18:00 (MST-7)
Magnitude: 64.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Mesonet station fblm8, fort belknap raws.

High Wind in BLAINE, MONTANA
From 20-DEC-20 09:18:00 to 20-DEC-20 09:18:00 (MST-7)
Magnitude: 50.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Mesonet station fblm8, fort belknap raws.

High Wind in CASCADE, MONTANA
From 20-DEC-20 15:19:00 to 20-DEC-20 15:19:00 (MST-7)
Magnitude: 64.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Station 4 N Belt.

High Wind in CASCADE, MONTANA
From 20-DEC-20 07:47:00 to 20-DEC-20 07:47:00 (MST-7)
Magnitude: 58.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Mhanging.

High Wind in CHOUTEAU, MONTANA
From 20-DEC-20 13:49:00 to 20-DEC-20 13:49:00 (MST-7)
Magnitude: 54.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Edwards.

High Wind in CHOUTEAU, MONTANA
From 20-DEC-20 13:15:00 to 20-DEC-20 13:15:00 (MST-7)
Magnitude: 53.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Mesonet station mtm02, 10.2 s loma (mt-meso).

High Wind in FERGUS, MONTANA
From 20-DEC-20 12:18:00 to 20-DEC-20 12:18:00 (MST-7)
Magnitude: 63.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Mesonet station mtden, denton (mt dot).

High Wind in FERGUS, MONTANA
From 20-DEC-20 12:54:00 to 20-DEC-20 12:54:00 (MST-7)
Magnitude: 59.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Asos station klwt, lewistown asos.

High Wind in GALLATIN, MONTANA
From 20-DEC-20 14:00:00 to 20-DEC-20 14:00:00 (MST-7)
Magnitude: 66.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Mesonet station gnfhy, 10.7 w emigrant (avalanche).

High Wind in GALLATIN, MONTANA
From 20-DEC-20 09:00:00 to 20-DEC-20 09:00:00 (MST-7)
Magnitude: 64.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Mesonet station bbslh, 10.2 ne bozeman (avalanche).

High Wind in NORTH ROCKY MOUNTAIN FRONT, MONTANA
From 19-DEC-20 16:22:00 to 19-DEC-20 16:22:00 (MST-7)
Magnitude: 68.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Mesonet station mtbrn two medicine bridge (mt dot).

High Wind in NORTH ROCKY MOUNTAIN FRONT, MONTANA
From 19-DEC-20 03:40:00 to 19-DEC-20 03:40:00 (MST-7)
Magnitude: 63.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Mesonet station mtbwg browning (mt dot).

High Wind in EASTERN GLACIER, MONTANA
From 20-DEC-20 04:56:00 to 20-DEC-20 04:56:00 (MST-7)
Magnitude: 55.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Asos station kctb, cut bank airport.

High Wind in EASTERN GLACIER, MONTANA
From 20-DEC-20 05:02:00 to 20-DEC-20 05:02:00 (MST-7)
Magnitude: 54.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Mesonet station ew5772, cut bank.

High Wind in HILL, MONTANA
From 20-DEC-20 05:45:00 to 20-DEC-20 05:45:00 (MST-7)
Magnitude: 55.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Mesonet station ew1937, goldstone.

High Wind in HILL, MONTANA
From 20-DEC-20 11:14:00 to 20-DEC-20 11:14:00 (MST-7)
Magnitude: 55.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Saddle butte.

High Wind in JUDITH BASIN, MONTANA
From 20-DEC-20 12:57:00 to 20-DEC-20 12:57:00 (MST-7)
Magnitude: 58.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Awos station k1bm, bravo.

High Wind in JUDITH BASIN, MONTANA
From 20-DEC-20 10:56:00 to 20-DEC-20 10:56:00 (MST-7)
Magnitude: 57.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Awos station k1cm, charlie.

High Wind in SOUTHERN ROCKY MOUNTAIN FRONT, MONTANA
From 19-DEC-20 05:44:00 to 19-DEC-20 05:44:00 (MST-7)
Magnitude: 69.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Upper Elk Creek.

High Wind in SOUTHERN LEWIS AND CLARK, MONTANA
From 19-DEC-20 10:59:00 to 19-DEC-20 10:59:00 (MST-7)
Magnitude: 58.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Goss.

High Wind in SOUTHERN ROCKY MOUNTAIN FRONT, MONTANA
From 20-DEC-20 00:00:00 to 20-DEC-20 00:00:00 (MST-7)
Magnitude: 55.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Fechter.

High Wind in MEAGHER, MONTANA
From 20-DEC-20 14:23:00 to 20-DEC-20 14:23:00 (MST-7)
Magnitude: 60.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Inger.

High Wind in MEAGHER, MONTANA
From 20-DEC-20 01:39:00 to 20-DEC-20 01:39:00 (MST-7)
Magnitude: 54.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Ef smith.

High Wind in EASTERN PONDERA, MONTANA
From 20-DEC-20 07:15:00 to 20-DEC-20 07:15:00 (MST-7)
Magnitude: 52.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Mesonet station mtm73, ledger n mda.

High Wind in TOOLE, MONTANA
From 19-DEC-20 01:59:00 to 19-DEC-20 01:59:00 (MST-7)
Magnitude: 61.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Fenger.

High Wind in TOOLE, MONTANA
From 20-DEC-20 05:30:00 to 20-DEC-20 05:30:00 (MST-7)
Magnitude: 53.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Mesonet station mtsun, sunburst (mt dot).

Dust Storm in CHOUTEAU, MONTANA
From 20-DEC-20 13:10:00 to 20-DEC-20 13:10:00 (MST-7)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

Mt department of transportation reports dust storm with zero visibility on us-87 from mile marker 13 to 27.

High Wind in SOUTHERN LEWIS AND CLARK, MONTANA
From 19-DEC-20 15:39:00 to 19-DEC-20 15:39:00 (MST-7)
Magnitude: 70.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Iron Ridge.