A stagnant weather pattern on August 23rd and 24th resulted in waves of heavy rain and severe thunderstorms.  A warm front pushed north during the afternoon of August 23rd.  A very unstable airmass with moderate shear caused thunderstorms to break out during the afternoon and continue through most of the overnight as a warm front moved north through the area.  Very large hail was the primary hazard with some of the supercell thunderstorms, although there were several reports of wind damage, one tornado 2 miles south-southeast of Leland, and torrential downpours with localized flooding.  Incredibly, three separate supercells tracked southeast through Sauk County almost along the same path.  Each supercell had a rotating wall cloud at its base, but only one supercell managed to spin up a brief tornado.  After a brief respite of only 3 hours during the morning hours of August 24th, more storms developed during the late morning and afternoon hours.  More heavy rain, large hail, damaging winds, and vivid lightning resulted from these storms.  Urban flooding in Dane and Kenosha counties caused a few hundred thousand dollars in structural damage.  Some two-day rainfall totals across Dane County include 5.70 inches in Oregon, 5.38 inches in Cottage Grove, 3.26 inches in Middleton, 2.77 inches at Beloit College, and 2.73 inches at Madison Truax Field.  Roughly 12,000 customers lost electrical power due to downed power lines and lightning strikes.

Hail in DANE, WISCONSIN
From 24-AUG-06 00:35:00 to 24-AUG-06 00:45:00 (CST)
Location: COTTAGE GROVE
Magnitude: 1.75 
Property damage: 2M
Reported by: COOP STATION

Large hail damage many homes and vehicles, resulting in an estimated 200 claims.  Some of the homes that sustained hail damage were just recently repaired due to damage inflicted by the April 13, 2006, hailstorm that dumped hail up to 3 to 4 inches in diameter on a path west to east across Dane County.

Hail in SAUK, WISCONSIN
From 23-AUG-06 18:55:00 to 23-AUG-06 18:55:00 (CST)
Location: LA VALLE
Magnitude: 0.75 
Reported by: TRAINED SPOTTER

Hail in KENOSHA, WISCONSIN
From 24-AUG-06 08:47:00 to 24-AUG-06 08:47:00 (CST)
Location: KENOSHA
Magnitude: 0.75 
Reported by: TRAINED SPOTTER

Hail in DANE, WISCONSIN
From 23-AUG-06 22:35:00 to 23-AUG-06 22:35:00 (CST)
Location: CROSS PLAINS
Magnitude: 0.75 
Reported by: TRAINED SPOTTER

Hail in DANE, WISCONSIN
From 23-AUG-06 22:45:00 to 23-AUG-06 22:45:00 (CST)
Location: COTTAGE GROVE
Magnitude: 0.75 
Reported by: GENERAL PUBLIC

Lightning in KENOSHA, WISCONSIN
From 24-AUG-06 11:15:00 to 24-AUG-06 11:15:00 (CST)
Location: KENOSHA
Property damage: 14M
Reported by: FIRE DEPT/RESCUE SQUAD

Several lightning strikes to several buildings caused structural fires and power outages.  A large apartment building, known as St. Catherine Commons, was struck by lightning.  The resultant fire severely damaged the building, displacing about 125 residents.

Hail in ROCK, WISCONSIN
From 24-AUG-06 01:30:00 to 24-AUG-06 01:30:00 (CST)
Location: JANESVILLE
Magnitude: 1.75 
Reported by: LAW ENFORCEMENT

Hail in SAUK, WISCONSIN
From 24-AUG-06 02:04:00 to 24-AUG-06 02:04:00 (CST)
Location: PRAIRIE DU SAC
Magnitude: 1.50 
Reported by: TRAINED SPOTTER

Hail in MARQUETTE, WISCONSIN
From 23-AUG-06 23:48:00 to 23-AUG-06 23:48:00 (CST)
Location: OXFORD
Magnitude: 1.75 
Reported by: GENERAL PUBLIC

Tornado in SAUK, WISCONSIN
From 23-AUG-06 20:02:00 to 23-AUG-06 20:02:00 (CST)
Location: LELAND
Tornado F-scale: F0
Crop damage: 5K
Reported by: AMATEUR RADIO

A brief F0 tornado spun up 2.0 miles SSE of Leland.  This tornado, seen by a team of advanced severe weather spotters who were chasing the associated supercell, damaged only some vegetation.

Hail in SAUK, WISCONSIN
From 23-AUG-06 18:55:00 to 23-AUG-06 18:55:00 (CST)
Location: LA VALLE
Magnitude: 0.88 
Reported by: TRAINED SPOTTER

Hail in DODGE, WISCONSIN
From 23-AUG-06 21:50:00 to 23-AUG-06 21:50:00 (CST)
Location: HORICON
Magnitude: 0.75 
Reported by: GENERAL PUBLIC

Hail in RACINE, WISCONSIN
From 23-AUG-06 13:48:00 to 23-AUG-06 13:48:00 (CST)
Location: WIND PT
Magnitude: 0.75 
Reported by: GENERAL PUBLIC

Hail in DANE, WISCONSIN
From 23-AUG-06 22:26:00 to 23-AUG-06 22:26:00 (CST)
Location: BLACK EARTH
Magnitude: 0.88 
Reported by: TRAINED SPOTTER

Hail in COLUMBIA, WISCONSIN
From 24-AUG-06 00:43:00 to 24-AUG-06 00:43:00 (CST)
Location: CAMBRIA
Magnitude: 1.00 
Reported by: TRAINED SPOTTER

Hail in ROCK, WISCONSIN
From 23-AUG-06 23:36:00 to 23-AUG-06 23:36:00 (CST)
Location: EVANSVILLE
Magnitude: 0.75 
Reported by: LAW ENFORCEMENT

Heavy Rain in COLUMBIA, WISCONSIN
From 24-AUG-06 00:00:00 to 24-AUG-06 00:20:00 (CST)
Location: PORTAGE
Property damage: 1K
Reported by: LAW ENFORCEMENT

Persistent heavy rain caused some basement flooding 3 miles north of Portage.

Hail in SAUK, WISCONSIN
From 23-AUG-06 20:04:00 to 23-AUG-06 20:05:00 (CST)
Location: LA VALLE
Magnitude: 1.00 
Reported by: TRAINED SPOTTER

Hail in KENOSHA, WISCONSIN
From 24-AUG-06 08:50:00 to 24-AUG-06 08:50:00 (CST)
Location: PLEASANT PRAIRIE
Magnitude: 0.88 
Reported by: TRAINED SPOTTER

Hail in SAUK, WISCONSIN
From 23-AUG-06 21:30:00 to 23-AUG-06 21:30:00 (CST)
Location: IRONTON
Magnitude: 1.00 
Reported by: GENERAL PUBLIC

Hail in SAUK, WISCONSIN
From 23-AUG-06 21:58:00 to 23-AUG-06 21:58:00 (CST)
Location: LELAND
Magnitude: 1.00 
Reported by: GENERAL PUBLIC

Hail in MARQUETTE, WISCONSIN
From 24-AUG-06 00:30:00 to 24-AUG-06 00:30:00 (CST)
Location: PACKWAUKEE
Magnitude: 1.00 
Reported by: GENERAL PUBLIC

Thunderstorm Wind in ROCK, WISCONSIN
From 24-AUG-06 03:30:00 to 24-AUG-06 03:35:00 (CST)
Location: BELOIT
Magnitude: 56 EG
Property damage: 5K
Reported by: NEWSPAPER

Trees down.  One fell onto a home, resulting in minor damage.

Flash Flood in KENOSHA, WISCONSIN
From 24-AUG-06 15:00:00 to 24-AUG-06 17:00:00 (CST)
Location: PADDOCK LAKE
Property damage: 10K
Reported by: EMERGENCY MANAGER

Torrential rainfall from thunderstorms caused flooding of roads and basements.

Hail in MILWAUKEE, WISCONSIN
From 23-AUG-06 14:52:00 to 23-AUG-06 14:52:00 (CST)
Location: MILWAUKEE
Magnitude: 0.75 
Reported by: GENERAL PUBLIC

Hail in JEFFERSON, WISCONSIN
From 24-AUG-06 01:04:00 to 24-AUG-06 01:04:00 (CST)
Location: LAKE MILLS
Magnitude: 0.75 
Reported by: GENERAL PUBLIC

Hail in DANE, WISCONSIN
From 23-AUG-06 21:46:00 to 23-AUG-06 21:46:00 (CST)
Location: MIDDLETON
Magnitude: 1.00 
Reported by: COOP STATION

Hail in WAUKESHA, WISCONSIN
From 24-AUG-06 00:34:00 to 24-AUG-06 00:34:00 (CST)
Location: BIG BEND
Magnitude: 1.00 
Reported by: COOP STATION

Thunderstorm Wind in IOWA, WISCONSIN
From 24-AUG-06 12:15:00 to 24-AUG-06 12:15:00 (CST)
Location: HIGHLAND
Magnitude: 50 EG
Reported by: POST OFFICE

Garbage cans were reported being airborne with large broken tree limbs.

Hail in DANE, WISCONSIN
From 24-AUG-06 02:18:00 to 24-AUG-06 02:18:00 (CST)
Location: CROSS PLAINS
Magnitude: 0.75 
Reported by: TRAINED SPOTTER

Hail in SAUK, WISCONSIN
From 23-AUG-06 21:28:00 to 23-AUG-06 21:35:00 (CST)
Location: LA VALLE
Magnitude: 1.00 
Reported by: TRAINED SPOTTER

Hail in COLUMBIA, WISCONSIN
From 24-AUG-06 01:20:00 to 24-AUG-06 01:20:00 (CST)
Location: RIO
Magnitude: 1.00 
Reported by: GENERAL PUBLIC

Thunderstorm Wind in DANE, WISCONSIN
From 24-AUG-06 02:40:00 to 24-AUG-06 02:40:00 (CST)
Location: MIDDLETON
Magnitude: 56 EG
Reported by: TRAINED SPOTTER

Trees down.

Hail in COLUMBIA, WISCONSIN
From 24-AUG-06 00:20:00 to 24-AUG-06 00:20:00 (CST)
Location: PARDEEVILLE
Magnitude: 0.75 
Reported by: TRAINED SPOTTER

Hail in SAUK, WISCONSIN
From 23-AUG-06 19:35:00 to 23-AUG-06 19:35:00 (CST)
Location: LOGANVILLE
Magnitude: 0.75 
Reported by: GENERAL PUBLIC

Hail in COLUMBIA, WISCONSIN
From 24-AUG-06 00:05:00 to 24-AUG-06 00:15:00 (CST)
Location: PORTAGE
Magnitude: 0.75 
Crop damage: 100K
Reported by: TRAINED SPOTTER

About 150 acres of corn crop were damaged in an area near STH 33, about 4 miles west of STH 22.

Hail in DANE, WISCONSIN
From 24-AUG-06 00:36:00 to 24-AUG-06 00:36:00 (CST)
Location: MADISON
Magnitude: 0.75 
Reported by: AMATEUR RADIO

Thunderstorm Wind in DANE, WISCONSIN
From 24-AUG-06 01:05:00 to 24-AUG-06 01:10:00 (CST)
Location: FITCHBURG
Magnitude: 56 EG
Reported by: LAW ENFORCEMENT

Trees reported down.

Thunderstorm Wind in COLUMBIA, WISCONSIN
From 24-AUG-06 00:12:00 to 24-AUG-06 00:12:00 (CST)
Location: PORTAGE
Magnitude: 52 EG
Reported by: TRAINED SPOTTER

Trees down.

Hail in DANE, WISCONSIN
From 24-AUG-06 00:22:00 to 24-AUG-06 00:22:00 (CST)
Location: MIDDLETON
Magnitude: 0.75 
Reported by: AMATEUR RADIO

Hail in DANE, WISCONSIN
From 24-AUG-06 04:13:00 to 24-AUG-06 04:23:00 (CST)
Location: ROXBURY
Magnitude: 1.75 
Reported by: AMATEUR RADIO

Hail in GREEN, WISCONSIN
From 24-AUG-06 13:24:00 to 24-AUG-06 13:24:00 (CST)
Location: MONTICELLO
Magnitude: 0.75 
Reported by: LAW ENFORCEMENT

Thunderstorm Wind in IOWA, WISCONSIN
From 24-AUG-06 12:35:00 to 24-AUG-06 12:35:00 (CST)
Location: REWEY
Magnitude: 50 EG
Reported by: POST OFFICE

Tree limbs down.

Lightning in DANE, WISCONSIN
From 24-AUG-06 13:00:00 to 24-AUG-06 13:00:00 (CST)
Location: COTTAGE GROVE
Property damage: 250K
Reported by: NEWSPAPER

A home was struck by a lightning bolt, and the resultant fire gutted the home.

Thunderstorm Wind in JEFFERSON, WISCONSIN
From 24-AUG-06 04:38:00 to 24-AUG-06 04:38:00 (CST)
Location: JOHNSON CREEK
Magnitude: 52 EG
Reported by: LAW ENFORCEMENT

Trees down.

Thunderstorm Wind in DODGE, WISCONSIN
From 24-AUG-06 01:05:00 to 24-AUG-06 01:05:00 (CST)
Location: BEAVER DAM
Magnitude: 56 EG
Reported by: GENERAL PUBLIC

Trees down.

Thunderstorm Wind in LAFAYETTE, WISCONSIN
From 24-AUG-06 13:00:00 to 24-AUG-06 13:00:00 (CST)
Location: ARGYLE
Magnitude: 52 EG
Reported by: LAW ENFORCEMENT

Trees down.

Thunderstorm Wind in DANE, WISCONSIN
From 24-AUG-06 00:40:00 to 24-AUG-06 00:40:00 (CST)
Location: COTTAGE GROVE
Magnitude: 56 EG
Property damage: 10K
Reported by: NEWSPAPER

Large trees down. One tree landed on a home.

Hail in DANE, WISCONSIN
From 24-AUG-06 00:35:00 to 24-AUG-06 00:35:00 (CST)
Location: MADISON
Magnitude: 0.75 
Reported by: NWS EMPLOYEE(OFF DUTY)

Flash Flood in RACINE, WISCONSIN
From 24-AUG-06 15:00:00 to 24-AUG-06 17:00:00 (CST)
Location: BURLINGTON
Property damage: 20K
Reported by: EMERGENCY MANAGER

Persistent thunderstorms producing torrential rain caused flooding from 2 miles east of Burlington to 2 miles west of Union Grove.  The water closed several roads and caused some basement flooding.  Radar estimated 4 to 5 inches of rainfall in this area and 3.71 inches of rain was reported in Burlington.

Lightning in KENOSHA, WISCONSIN
From 24-AUG-06 11:20:00 to 24-AUG-06 11:20:00 (CST)
Location: PLEASANT PRAIRIE
Property damage: 150K
Reported by: FIRE DEPT/RESCUE SQUAD

Several lightning strikes to several buildings caused structural fires and power outages.

Hail in DANE, WISCONSIN
From 24-AUG-06 01:10:00 to 24-AUG-06 01:10:00 (CST)
Location: ALBION
Magnitude: 1.00 
Reported by: LAW ENFORCEMENT

Hail in JEFFERSON, WISCONSIN
From 24-AUG-06 03:15:00 to 24-AUG-06 03:15:00 (CST)
Location: WATERLOO
Magnitude: 0.75 
Reported by: LAW ENFORCEMENT

Hail in ROCK, WISCONSIN
From 24-AUG-06 03:21:00 to 24-AUG-06 03:35:00 (CST)
Location: FOOTVILLE
Magnitude: 2.50 
Reported by: LAW ENFORCEMENT

Large hail ranging from 1.00 inch to 2.50 inches fell from 1 mile west of Footville to 4 miles west of Beloit.

Heavy Rain in DANE, WISCONSIN
From 24-AUG-06 12:00:00 to 24-AUG-06 14:00:00 (CST)
Location: MADISON
Reported by: LAW ENFORCEMENT

More heavy rain of 1 to 2 inches on already saturated ground caused some minor urban flooding from around the Madison area to Cottage Grove.  One car was stalled after trying to drive through flood waters.

Heavy Rain in KENOSHA, WISCONSIN
From 24-AUG-06 11:00:00 to 24-AUG-06 11:00:00 (CST)
Location: SOMERS
Reported by: LAW ENFORCEMENT

Minor street flooding resulted after 1 inch of rain fell on top of saturated ground.

Hail in ROCK, WISCONSIN
From 24-AUG-06 02:41:00 to 24-AUG-06 02:41:00 (CST)
Location: MILTON
Magnitude: 0.75 
Reported by: LAW ENFORCEMENT

Hail in DANE, WISCONSIN
From 24-AUG-06 02:40:00 to 24-AUG-06 02:40:00 (CST)
Location: MADISON
Magnitude: 1.00 
Reported by: TRAINED SPOTTER

Hail in COLUMBIA, WISCONSIN
From 24-AUG-06 04:10:00 to 24-AUG-06 04:10:00 (CST)
Location: OKEE
Magnitude: 1.25 
Reported by: LAW ENFORCEMENT

Hail in SAUK, WISCONSIN
From 24-AUG-06 03:15:00 to 24-AUG-06 03:15:00 (CST)
Location: LA VALLE
Magnitude: 1.00 
Reported by: LAW ENFORCEMENT

Hail in MARQUETTE, WISCONSIN
From 23-AUG-06 20:50:00 to 23-AUG-06 20:50:00 (CST)
Location: MONTELLO
Magnitude: 0.75 
Reported by: LAW ENFORCEMENT

Hail in SAUK, WISCONSIN
From 24-AUG-06 03:54:00 to 24-AUG-06 03:54:00 (CST)
Location: BARABOO
Magnitude: 1.00 
Reported by: LAW ENFORCEMENT

Hail in SAUK, WISCONSIN
From 23-AUG-06 20:31:00 to 23-AUG-06 20:31:00 (CST)
Location: LOGANVILLE
Magnitude: 1.75 
Reported by: LAW ENFORCEMENT

Hail in DANE, WISCONSIN
From 24-AUG-06 04:43:00 to 24-AUG-06 04:43:00 (CST)
Location: MADISON
Magnitude: 0.75 
Reported by: AMATEUR RADIO

Lightning in DANE, WISCONSIN
From 24-AUG-06 13:00:00 to 24-AUG-06 14:00:00 (CST)
Location: MARSHALL
Property damage: 60K
Reported by: NEWSPAPER

Twelve cows were killed by a lightning strike.

Lightning in WALWORTH, WISCONSIN
From 24-AUG-06 13:30:00 to 24-AUG-06 13:30:00 (CST)
Location: LAKE GENEVA
Property damage: 10K
Reported by: NEWSPAPER

A home's roof antenna was struck by lightning, resulting in a minor roof fire.

Lightning in WAUKESHA, WISCONSIN
From 24-AUG-06 13:15:00 to 24-AUG-06 13:15:00 (CST)
Location: MUSKEGO
Reported by: NEWSPAPER

A women was struck by lightning in a parking lot of a business.  She was treated at a local hospital and released.