A cold front crossed into the northwest quarter of Minnesota late on the night of the 18th into the early morning hours of the 19th. Thunderstorms fired up along the boundary, from Red Lake Falls to Fosston to Bemidji, producing large hail, strong winds, and heavy amounts of rain. Nearly continuous lightning lit up the night sky.

Hail in RED LAKE, MINNESOTA
From 18-AUG-11 23:25:00 to 18-AUG-11 23:28:00 (CST-6)
Location: RED LAKE FALLS
Magnitude: 1.00 
Reported by: Trained Spotter

Mainly dime to nickel sized hail fell along with a few quarter sized hailstones.

Hail in POLK, MINNESOTA
From 18-AUG-11 23:45:00 to 18-AUG-11 23:45:00 (CST-6)
Location: MENTOR
Magnitude: 1.00 
Reported by: Trained Spotter

Hail in POLK, MINNESOTA
From 18-AUG-11 23:55:00 to 18-AUG-11 23:55:00 (CST-6)
Location: ERSKINE
Magnitude: 1.00 
Reported by: Trained Spotter

Quite a bit of nickel to quarter sized hail fell.

Hail in POLK, MINNESOTA
From 19-AUG-11 00:05:00 to 19-AUG-11 00:05:00 (CST-6)
Location: MC INTOSH
Magnitude: 1.75 
Reported by: Broadcast Media

Hail in BECKER, MINNESOTA
From 19-AUG-11 00:20:00 to 19-AUG-11 00:20:00 (CST-6)
Location: TWO INLETS
Magnitude: 1.00 
Reported by: Public

The hail was still in the gutters at sunrise.

Hail in POLK, MINNESOTA
From 19-AUG-11 00:25:00 to 19-AUG-11 00:25:00 (CST-6)
Location: FOSSTON
Magnitude: 1.00 
Reported by: Broadcast Media

Hail in BELTRAMI, MINNESOTA
From 19-AUG-11 00:30:00 to 19-AUG-11 00:30:00 (CST-6)
Location: PINEWOOD
Magnitude: 0.88 
Reported by: Amateur Radio

Lots of dime to nickel sized hail fell along with very heavy rain.

Hail in CLEARWATER, MINNESOTA
From 19-AUG-11 00:35:00 to 19-AUG-11 00:35:00 (CST-6)
Location: LAKE ITASCA
Magnitude: 1.00 
Reported by: Trained Spotter

Marble to quarter sized hail fell at Itasca State Park.

Hail in BELTRAMI, MINNESOTA
From 19-AUG-11 00:40:00 to 19-AUG-11 00:40:00 (CST-6)
Location: SCRIBNER
Magnitude: 1.00 
Reported by: Law Enforcement

Lots of quarter sized hail fell along highway 89.

Hail in BELTRAMI, MINNESOTA
From 19-AUG-11 01:00:00 to 19-AUG-11 01:00:00 (CST-6)
Location: BEMIDJI
Magnitude: 1.50 
Reported by: Trained Spotter

Thunderstorm Wind in BELTRAMI, MINNESOTA
From 19-AUG-11 01:00:00 to 19-AUG-11 01:00:00 (CST-6)
Location: BEMIDJI
Magnitude: 61.00 EG
Reported by: Trained Spotter

Very strong winds occurred with the large hail.

Thunderstorm Wind in BELTRAMI, MINNESOTA
From 19-AUG-11 01:04:00 to 19-AUG-11 01:04:00 (CST-6)
Location: BEMIDJI
Magnitude: 55.00 EG
Reported by: Amateur Radio

Large trees were blown down along the south side of Lake Bemidji.

Thunderstorm Wind in BELTRAMI, MINNESOTA
From 19-AUG-11 01:09:00 to 19-AUG-11 01:09:00 (CST-6)
Location: BEMIDJI
Magnitude: 55.00 EG
Reported by: Law Enforcement

Some siding was blown off of a building near the Pamida store south of Lake Bemidji.

Thunderstorm Wind in BELTRAMI, MINNESOTA
From 19-AUG-11 01:28:00 to 19-AUG-11 01:28:00 (CST-6)
Location: BEMIDJI
Magnitude: 55.00 EG
Reported by: Law Enforcement

There were reports of power poles snapped and power lines down in the Nymore area of southeast Bemidji and southeast Beltrami County.

Flash Flood in BELTRAMI, MINNESOTA
From 19-AUG-11 01:35:00 to 19-AUG-11 03:35:00 (CST-6)
Location: BEMIDJI
Flood cause: Heavy Rain
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Several streets south of downtown Bemidji had 1 to 2 feet of water flowing in them and at least one car was stranded.

Thunderstorm Wind in BELTRAMI, MINNESOTA
From 19-AUG-11 01:20:00 to 19-AUG-11 01:20:00 (CST-6)
Location: PENNINGTON
Magnitude: 55.00 EG
Reported by: Law Enforcement

Many trees were blown down and power poles snapped along Roosevelt Road and around northern Cass Lake.