Deep southerly flow brought sufficient instability and shear to the region. An approaching trough provided sufficient forcing for ascent, resulting in a few severe thunderstorms across western portions of North-central Montana. One supercell dominated, beginning near Lincoln, travelling northeastward, finally crossing the Canadian border at the Blaine/Hill County border.

Thunderstorm Wind in HILL, MONTANA
From 18-JUN-22 16:47:00 to 18-JUN-22 16:47:00 (MST-7)
Location: HAURE AFS
Magnitude: 56.00 EG
Property damage: 20.00K
Crop damage: 0.00K
Reported by: Public

Two power poles snapped at the base. Road signs reported to be blown over.

Thunderstorm Wind in CASCADE, MONTANA
From 18-JUN-22 14:15:00 to 18-JUN-22 14:15:00 (MST-7)
Location: VAUGHN
Magnitude: 70.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Storm Survey

Nws survey team determined damaging straight line winds with speeds of around 80 mph occurred across an area approx 1.7 miles long and 1.1 miles wide. Numerous wooden power poles snapped along i-15. Flattened grass and shrubs across the area. Pea size hail and water flooded local ditches and streams. Time based on radar.

Hail in CASCADE, MONTANA
From 18-JUN-22 14:00:00 to 18-JUN-22 14:00:00 (MST-7)
Location: FT SHAW
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Estimated hail size of a penny from the public.

Hail in CASCADE, MONTANA
From 18-JUN-22 13:52:00 to 18-JUN-22 13:52:00 (MST-7)
Location: SIMMS
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reports quarter sized hail. Time estimated by radar.

Lightning in LEWIS AND CLARK, MONTANA
From 18-JUN-22 13:30:00 to 18-JUN-22 13:30:00 (MST-7)
Location: GILMAN
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Park/Forest Service

A 34 year old female struck by lightning, which also injured a 40 year old male and another male of unknown age. Individuals were driving a vehicle that had a kayak strapped to top of vehicle. Strap came loose and the group pulled over and got out to tighten the strap when they were struck. Female was flung six feet, struck head on rocks, and stopped breathing. CPR was performed before individual was air lifted to salt lake city where she remains in the icu. The 40 year old male suffered burns and other individual suffered minor injuries. Time of event is estimated.

Hail in CASCADE, MONTANA
From 18-JUN-22 13:05:00 to 18-JUN-22 13:05:00 (MST-7)
Location: SUN RIVER
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Video showing hail was taken in Sun River. Person who took the video reported up to quarter sized hail. Time estimated from radar.

Thunderstorm Wind in FERGUS, MONTANA
From 18-JUN-22 18:15:00 to 18-JUN-22 18:15:00 (MST-7)
Location: ROY
Magnitude: 56.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Mesonet station mtm42 BLM roy measured a 64 mph gust.

Thunderstorm Wind in HILL, MONTANA
From 18-JUN-22 16:27:00 to 18-JUN-22 16:27:00 (MST-7)
Location: HAURE AFS
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public report of two power poles snapped at the base on mt highway 232 at mile marker 21. Additionally, signs were reported to be blown over. Time estimated via radar.

Thunderstorm Wind in TETON, MONTANA
From 18-JUN-22 14:25:00 to 18-JUN-22 14:25:00 (MST-7)
Location: POWER
Magnitude: 67.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Awos station k1jm juliett observed a peak wind gust of 67 knots.

Thunderstorm Wind in CASCADE, MONTANA
From 18-JUN-22 14:12:00 to 18-JUN-22 14:12:00 (MST-7)
Location: VAUGHN
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Numerous power poles snapped along I-15. Pea size hail and water filling the ditch. Time/location estimated.

Thunderstorm Wind in TETON, MONTANA
From 18-JUN-22 13:45:00 to 18-JUN-22 13:45:00 (MST-7)
Location: AGAWAM
Magnitude: 50.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Mesonet station ricmt Rice Ridge observed a 50kt gust.