Growing clusters of strong to severe thunderstorms over northeast and east-central Wisconsin interacted with a Lake Michigan lake breeze boundary.  The storms became better organized and grew and became more widespread, producing large hail, wind damage and torrential rainfall that led to some minor flooding.
Winnebago County was hardest hit by the storms with hail to golf ball size, wind gusts of 60 to 70 mph and heavy rainfall.  Damage there was estimated at $250,000.  Construction signs, barrels and a crane were toppled by the thunderstorm winds and approximately 500 homes sustained at least minor damage from the hail.  Torrential rainfall caused minor street flooding in the Oshkosh area and ponding of water on part of U.S. Highway 41.  As many as four homes in the county may have been struck by lightning during the storms.

Hail in WAUPACA, WISCONSIN
From 02-JUL-12 15:42:00 to 02-JUL-12 15:44:00 (CST-6)
Location: CLINTONVILLE
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Ping pong ball size hail fell at Clintonville.

Hail in WAUPACA, WISCONSIN
From 02-JUL-12 16:30:00 to 02-JUL-12 16:30:00 (CST-6)
Location: NEW LONDON
Magnitude: 1.50 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Walnut size hail fell at New London.

Hail in WAUPACA, WISCONSIN
From 02-JUL-12 16:45:00 to 02-JUL-12 16:45:00 (CST-6)
Location: NEW LONDON
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Hail up to quarter size fell at New London.

Hail in OUTAGAMIE, WISCONSIN
From 02-JUL-12 16:57:00 to 02-JUL-12 16:57:00 (CST-6)
Location: HORTONVILLE
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Penny size hail fell at Hortonville.

Hail in CALUMET, WISCONSIN
From 02-JUL-12 17:43:00 to 02-JUL-12 17:43:00 (CST-6)
Location: DARBOY
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Nickel size hail fell at Darboy.

Thunderstorm Wind in WINNEBAGO, WISCONSIN
From 02-JUL-12 17:42:00 to 02-JUL-12 17:42:00 (CST-6)
Location: LARSEN
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorms produced a wind gust to 60 mph as they passed northeast of Winneconne.

Thunderstorm Wind in WINNEBAGO, WISCONSIN
From 02-JUL-12 17:48:00 to 02-JUL-12 17:48:00 (CST-6)
Location: OSHKOSH
Magnitude: 61.00 EG
Property damage: 20.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorms produced large hail and wind gusts to 70 mph in Oshkosh.  The gust caused a canopy to collapse at a car rental business, damaging five cars.

Thunderstorm Wind in WINNEBAGO, WISCONSIN
From 02-JUL-12 17:50:00 to 02-JUL-12 17:50:00 (CST-6)
Location: OSHKOSH
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorms produced wind gusts to 60 mph that downed large tree limbs along 9th Avenue in Oshkosh.

Thunderstorm Wind in WINNEBAGO, WISCONSIN
From 02-JUL-12 17:30:00 to 02-JUL-12 17:30:00 (CST-6)
Location: LARSEN
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorm wind gusts downed trees on Oakwood Road west of Neenah.

Thunderstorm Wind in FOREST, WISCONSIN
From 02-JUL-12 19:00:00 to 02-JUL-12 19:00:00 (CST-6)
Location: WABENO
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Thunderstorm winds downed trees near the intersection of STH 52 and CTH W.

Thunderstorm Wind in WINNEBAGO, WISCONSIN
From 02-JUL-12 18:28:00 to 02-JUL-12 18:28:00 (CST-6)
Location: FISK
Magnitude: 61.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorms produced wind gusts of 60 to 70 mph near Oshkosh.

Hail in WINNEBAGO, WISCONSIN
From 02-JUL-12 17:48:00 to 02-JUL-12 18:00:00 (CST-6)
Location: OSHKOSH
Magnitude: 1.75 
Property damage: 250.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Thunderstorms produced golf ball size hail as they passed through Oshkosh. Approximately 500 homes and two dozen vehicles sustained at least minor damage as a result of the large hail in east-central Winnebago County.

Thunderstorm Wind in WINNEBAGO, WISCONSIN
From 02-JUL-12 18:08:00 to 02-JUL-12 18:08:00 (CST-6)
Location: (OSH)WITTMAN FLD OSH
Magnitude: 51.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Thunderstorms produced a wind gust of 59 mph at Wittman Regional Airport in Oshkosh.

Heavy Rain in WINNEBAGO, WISCONSIN
From 02-JUL-12 18:11:00 to 02-JUL-12 18:42:00 (CST-6)
Location: (OSH)WITTMAN FLD OSH
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Thunderstorms moving through Winnebago County produced 1.31 inches of rain in just 31 minutes at Wittman Regional Airport.

Hail in WAUPACA, WISCONSIN
From 02-JUL-12 16:05:00 to 02-JUL-12 16:05:00 (CST-6)
Location: NEW LONDON
Magnitude: 0.88 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Nickel size hail fell north of New London.