A cold front moving through the region generated strong to severe thunderstorms over portions of west and central Upper Michigan on the afternoon of the 20th.

Hail in HOUGHTON, MICHIGAN
From 20-MAY-12 15:10:00 to 20-MAY-12 15:12:00 (EST-5)
Location: JACOBSVILLE
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Thunderstorm Wind in DICKINSON, MICHIGAN
From 20-MAY-12 15:30:00 to 20-MAY-12 15:33:00 (CST-6)
Location: FLOODWOOD
Magnitude: 52.00 EG
Property damage: 1.00K
Crop damage: 0.00K
Reported by: Public

Winds estimated at 60 mph knocked over a 24-inch diameter white pine tree six miles south of Witch Lake.

Thunderstorm Wind in MARQUETTE, MICHIGAN
From 20-MAY-12 16:34:00 to 20-MAY-12 16:38:00 (EST-5)
Location: WITCH LAKE
Magnitude: 52.00 EG
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Public

Trees were knocked down across Highway M-95 along the Marquette/Dickinson County line.

Thunderstorm Wind in MARQUETTE, MICHIGAN
From 20-MAY-12 16:46:00 to 20-MAY-12 16:49:00 (EST-5)
Location: NATIONAL MINE
Magnitude: 50.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Very strong winds knocked down small tree limbs and blew patio furniture across the yard.

Hail in DICKINSON, MICHIGAN
From 20-MAY-12 16:04:00 to 20-MAY-12 16:06:00 (CST-6)
Location: (IMT)IRON MTN ARPT
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in MARQUETTE, MICHIGAN
From 20-MAY-12 18:07:00 to 20-MAY-12 18:09:00 (EST-5)
Location: (SAW)KI SAWYER AFB G
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail was reported near the Sawyer Airport.

Hail in GOGEBIC, MICHIGAN
From 20-MAY-12 11:35:00 to 20-MAY-12 11:38:00 (CST-6)
Location: IRONWOOD
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Thunderstorm Wind in MARQUETTE, MICHIGAN
From 20-MAY-12 16:52:00 to 20-MAY-12 16:56:00 (EST-5)
Location: NATIONAL MINE
Magnitude: 55.00 EG
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Several trees were knocked down along County Road 581.

Lightning in DICKINSON, MICHIGAN
From 20-MAY-12 16:30:00 to 20-MAY-12 18:30:00 (CST-6)
Location: IRON MTN
Property damage: 30.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

A lightning strike from thunderstorms caused a house fire in Iron Mountain on the evening of the 20th.  The home sustained damage in numerous areas, but firefighters were able to keep the damage contained to the second floor and attic.  The Iron Mountain Police Department, Beacon Ambulance and Wisconsin Electric were also at the scene of the fire to assist.

Hail in HOUGHTON, MICHIGAN
From 20-MAY-12 12:17:00 to 20-MAY-12 12:19:00 (EST-5)
Location: STANWOOD
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in HOUGHTON, MICHIGAN
From 20-MAY-12 12:30:00 to 20-MAY-12 12:32:00 (EST-5)
Location: QUINCY MILL
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Hail in HOUGHTON, MICHIGAN
From 20-MAY-12 12:30:00 to 20-MAY-12 12:32:00 (EST-5)
Location: DOLLAR BAY
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in HOUGHTON, MICHIGAN
From 20-MAY-12 12:45:00 to 20-MAY-12 12:48:00 (EST-5)
Location: CALUMET
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in ONTONAGON, MICHIGAN
From 20-MAY-12 14:57:00 to 20-MAY-12 15:00:00 (EST-5)
Location: WAINOLA
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Gusts up to 40 mph were reported with the storm.

Lightning in MARQUETTE, MICHIGAN
From 20-MAY-12 17:00:00 to 20-MAY-12 18:00:00 (EST-5)
Location: ISHPEMING
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Lightning and high wind from thunderstorms caused more than 200 customers to lose power in Ishpeming.

Heavy Rain in ONTONAGON, MICHIGAN
From 20-MAY-12 11:00:00 to 20-MAY-12 19:30:00 (EST-5)
Location: FIRESTEEL
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

The observer ten miles east of Ontonagon measured 1.75 inches of total rainfall.  A small creek on the residence was reported over its banks.  The observer at Rockland measured 2.80 inches of storm total rainfall.

Strong Wind in ALGER, MICHIGAN
From 20-MAY-12 16:30:00 to 20-MAY-12 17:15:00 (EST-5)
Magnitude: 44.00 MG
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Strong south winds ahead of a cold front caused downed power lines and knocked out power to more than 1200 customers in Munising.

Hail in MARQUETTE, MICHIGAN
From 20-MAY-12 18:21:00 to 20-MAY-12 18:23:00 (EST-5)
Location: SAND RIVER
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail was reported near Shot Point along Highway M-28.

Hail in DICKINSON, MICHIGAN
From 20-MAY-12 16:06:00 to 20-MAY-12 16:08:00 (CST-6)
Location: GRANITE BLUFF
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Hail in GOGEBIC, MICHIGAN
From 20-MAY-12 11:34:00 to 20-MAY-12 11:39:00 (CST-6)
Location: HURLEY
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail lasted five minutes.