An area of low pressure and a cold front moved across the Northland on the afternoon and evening of the 18th. Ahead of the cold front, dew points surged into the 70s and, coupled with the cold front, led to the development of a few supercell thunderstorms that moved across the region. The storms developed over north-central Minnesota during the afternoon and pushed eastward through northwest Wisconsin during the evening hours producing damaging winds and large hail as they pushed across the area.

Hail in CASS, MINNESOTA
From 18-JUL-20 17:40:00 to 18-JUL-20 17:42:00 (CST-6)
Location: OUTING
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in CASS, MINNESOTA
From 18-JUL-20 17:40:00 to 18-JUL-20 17:42:00 (CST-6)
Location: OUTING
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in ST. LOUIS, MINNESOTA
From 18-JUL-20 18:03:00 to 18-JUL-20 18:05:00 (CST-6)
Location: TOIVOLA
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in ST. LOUIS, MINNESOTA
From 18-JUL-20 18:09:00 to 18-JUL-20 18:11:00 (CST-6)
Location: TOIVOLA
Magnitude: 2.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in ST. LOUIS, MINNESOTA
From 18-JUL-20 18:25:00 to 18-JUL-20 18:27:00 (CST-6)
Location: SHAW
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in ST. LOUIS, MINNESOTA
From 18-JUL-20 18:30:00 to 18-JUL-20 18:32:00 (CST-6)
Location: SHAW
Magnitude: 3.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in ST. LOUIS, MINNESOTA
From 18-JUL-20 18:33:00 to 18-JUL-20 18:35:00 (CST-6)
Location: COTTON
Magnitude: 1.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Hail in ST. LOUIS, MINNESOTA
From 18-JUL-20 18:35:00 to 18-JUL-20 18:37:00 (CST-6)
Location: WHITEFACE
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

Hail in ST. LOUIS, MINNESOTA
From 18-JUL-20 18:35:00 to 18-JUL-20 18:37:00 (CST-6)
Location: COTTON
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Hail in ST. LOUIS, MINNESOTA
From 18-JUL-20 18:45:00 to 18-JUL-20 18:47:00 (CST-6)
Location: ISLAND LAKE
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in CARLTON, MINNESOTA
From 18-JUL-20 19:13:00 to 18-JUL-20 19:15:00 (CST-6)
Location: BARNUM
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in CARLTON, MINNESOTA
From 18-JUL-20 19:18:00 to 18-JUL-20 19:20:00 (CST-6)
Location: NEMADJI
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in CARLTON, MINNESOTA
From 18-JUL-20 19:20:00 to 18-JUL-20 19:22:00 (CST-6)
Location: MAHTOWA
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in PINE, MINNESOTA
From 18-JUL-20 19:33:00 to 18-JUL-20 19:35:00 (CST-6)
Location: STURGEON LAKE
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in COOK, MINNESOTA
From 19-JUL-20 00:03:00 to 19-JUL-20 00:05:00 (CST-6)
Location: GRAND PORTAGE
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Other Federal Agency

Thunderstorm Wind in ST. LOUIS, MINNESOTA
From 18-JUL-20 18:36:00 to 18-JUL-20 18:38:00 (CST-6)
Location: COTTON
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: State Official

Two trees were downed onto power lines.

Thunderstorm Wind in ST. LOUIS, MINNESOTA
From 18-JUL-20 18:50:00 to 18-JUL-20 18:52:00 (CST-6)
Location: ISLAND LAKE
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Multiple trees were downed by the storm on the north side of Island Lake.

Thunderstorm Wind in ST. LOUIS, MINNESOTA
From 18-JUL-20 18:55:00 to 18-JUL-20 18:57:00 (CST-6)
Location: ISLAND LAKE
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Eight large trees were downed across County Road 4 and Vermilion Trail.

Thunderstorm Wind in ST. LOUIS, MINNESOTA
From 18-JUL-20 18:56:00 to 18-JUL-20 18:58:00 (CST-6)
Location: ISLAND LAKE
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Two aspen trees 6 inches in diameter were downed by the winds.

Thunderstorm Wind in ST. LOUIS, MINNESOTA
From 18-JUL-20 19:05:00 to 18-JUL-20 19:07:00 (CST-6)
Location: PEQUAYWAN LAKE
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Several trees were snapped in the storm with one being a 14 inch diameter spruce tree.

Thunderstorm Wind in AITKIN, MINNESOTA
From 18-JUL-20 22:08:00 to 18-JUL-20 22:10:00 (CST-6)
Location: MC GREGOR
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Several large trees were downed a few miles west of McGregor.