Storm Record · Columbia, Dane, Dodge, Jefferson, Walworth, Waukesha Counties

June 12, 2013: Straight-line wind across six counties

1″
Largest hail
81mph
Strongest gust
11
NWS reports

What the National Weather Service recorded

Discrete supercell thunderstorms congealed into a line of severe thunderstorms over southwest Wisconsin that produced damaging wind gusts and large hail. The line of storms tracked through southern Wisconsin along and just north of a nearly-stationary warm front near the Wisconsin/Illinois border. Strong forcing for ascent was provided by the differential cyclonic vorticity advection associated with a compact mid/upper level trough. Bulk shear in the 0-6 km layer was on the order of 50-60 knots. In addition to the damaging winds and large hail, precipitable water values approached 2 inches, giving the storms sufficient moisture to produce heavy rainfall on the order of 1 to 2 inches in under one hour that caused localized street flooding.

Source: NOAA Storm Events Database · episode 76647

Every report, in the Weather Service's words

Where It Hit

Location County Hazard Size Report
Portage (5 SW) Columbia Wind 81 mph wind The Columbia County 911 Call Center reported approximately 100 trees were blown down, many power lines downed and scattered clusters of damage along a 17 mile-wide path from 5 miles southwest of Portage to Columbus from damaging thunderstorm wind gusts that were estimated up to 80 mph. A trained spotter recrded a 71 mph wind gust in Pardeeville. The roof was blown off a home and a garage was destroyed in Fall River. A home was destroyed and 2 houses damaged in the Town of Dakorra. Heavy rain accompanying the storms, with 1.58 inches measured in 45 minutes 3 miles east of Poynette, produced street flooding in Portage and Pardeeville.
Fox Lake (5 SW) Dodge Wind 70 mph wind The Dodge County Emergency Manager reported many trees and power lines were blown down along a 10 mile-wide path from 5 miles southwest of Fox Lake to 4 miles south of Juneau from damaging thunderstorm wind gusts that were estimated up to 70 mph (61 knots).
Marshall (7 N) Dane Wind 70 mph wind A trained spotter reported many large trees were blown down 7 miles north of Marshall from damaging thunderstorm wind gusts that were estimated up to 70 mph (61 knots).
Waterloo Jefferson Wind 64 mph wind The Jefferson County Emergency Manager reported many trees and power lines were blown down in Waterloo from damaging thunderstorm wind gusts that were estimated up to 65 mph ( knots).
Ft Atkinson Jefferson Wind 64 mph wind The Jefferson County Emergency Manager reported a couple of large trees and power lines were blown down in Ft. Atkinson from damaging thunderstorm wind gusts that were estimated up to 65 mph (56 knots).
Pewaukee Waukesha Wind 64 mph wind Law enforcement officials reported trees and power lines were blown down along a scattered path from Pewaukee to Eagle from damaging thunderstorm wind gusts that were estimated up to 65 mph (56 knots). Tree debris took down a power line in Eagle.
Brookfield Waukesha Wind 64 mph wind The Waukesha County Emergency Manager reported trees and power lines were blown down in Brookfield from damaging thunderstorm wind gusts that were estimated up to 65 mph (56 knots). One tree fell onto a church roof causing damage to the roof.
Watertown Jefferson Wind 60 mph wind The Jefferson County Emergency Manager reported trees and power lines were blown down in Watertown from damaging thunderstorm wind gusts that were estimated up to 60 mph (52 knots).
Williams Bay (1 ENE) Walworth Hail 1" hail An ham radio operator reported hail up to 1 inch 1 mile east-northeast of Williams Bay.
Williams Bay Walworth Hail 0.88" hail A law enforcement official reported hail up to 0.88 of an inch on the campus of George Williams College.
Rio (1 W) Columbia Hail 0.75" hail A trained spotter reported hail up to 3/4 of an inch 1 mile west of Rio.
Source: NOAA Storm Events Database, Wisconsin

Service areas this storm touched