Increasing warm air advection and moisture transport on a 50 to 60 knot low-level jet, with increasing instability under steepening mid-level lapse rates, produced elevated thunderstorms with large hail during the early morning hours of June 8th. As the nocturnal low level inversion mixed out with daytime heating during the mid-morning hours, the storms became surface based, with damaging wind gusts as well as large hail. Additionally, the elevated nature of the showers and thunderstorms, especially in far southern Wisconsin, caused the rain underneath to evaporate before reaching the ground. The evaporated rain cooled the air below the cloud base and caused it to accelerate toward the ground, creating isolated heat bursts in Green and Rock counties with damaging wind gusts that downed trees and power lines, and also rapidly raised air temperatures 10 to 20 degrees F.

Hail in FOND DU LAC, WISCONSIN
From 08-JUN-11 04:50:00 to 08-JUN-11 04:50:00 (CST-6)
Location: FOND DU LAC
Magnitude: 0.75 
Reported by: Emergency Manager

Hail in WASHINGTON, WISCONSIN
From 08-JUN-11 08:46:00 to 08-JUN-11 08:49:00 (CST-6)
Location: HARTFORD
Magnitude: 1.00 
Reported by: Trained Spotter

Some vehicles received minor denting.

Thunderstorm Wind in WASHINGTON, WISCONSIN
From 08-JUN-11 06:50:00 to 08-JUN-11 06:50:00 (CST-6)
Location: SLINGER
Magnitude: 56.00 EG
Reported by: Law Enforcement

Trees were blown over, large tree branches were broken, and some power lines were brought down.

Hail in JEFFERSON, WISCONSIN
From 08-JUN-11 08:22:00 to 08-JUN-11 08:22:00 (CST-6)
Location: JOHNSON CREEK
Magnitude: 0.75 
Reported by: Trained Spotter

Hail in DODGE, WISCONSIN
From 08-JUN-11 08:30:00 to 08-JUN-11 08:30:00 (CST-6)
Location: LEBANON
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Hail in LAFAYETTE, WISCONSIN
From 08-JUN-11 07:10:00 to 08-JUN-11 07:10:00 (CST-6)
Location: ARGYLE
Magnitude: 0.75 
Reported by: Post Office

Thunderstorm Wind in GREEN, WISCONSIN
From 08-JUN-11 09:20:00 to 08-JUN-11 09:30:00 (CST-6)
Location: MONROE
Magnitude: 61.00 EG
Property damage: 200.00K
Crop damage: 0.00K
Reported by: Law Enforcement

This was a heat burst - generated by a decaying convective rain shower band which resulted in evaporation of most of the rain that caused gusty southwest winds and rising temperatures of 10 to 20 degrees F.  Large trees were blown down in Albany, and 2 buildings in Monroe were damaged.  Additionally, there were scattered reports of broken power poles and power lines.  The damage swath was about 5 miles wide.

Thunderstorm Wind in ROCK, WISCONSIN
From 08-JUN-11 09:35:00 to 08-JUN-11 10:00:00 (CST-6)
Location: EVANSVILLE
Magnitude: 61.00 EG
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Law Enforcement

This was a heat burst - generated by a decaying convective rain shower band which resulted in evaporation of most of the rain that caused gusty southwest winds and rising temperatures of 10 to 20 degrees F.  Two trailers in Edgerton were blown over and damaged: one was construction trailer and the other a semi-truck trailer. Also - a racetrack concession stand was demolished by the winds.  Additionally, a few large trees were blown down and broken tree limbs knocked some power lines down.  The damage swath was about 5 miles wide.