Storm Record · Columbia, Dane, Dodge, Sauk, Walworth Counties

May 30, 2013: Straight-line wind across five counties

1″
Largest hail
70mph
Strongest gust
12
NWS reports

What the National Weather Service recorded

Individual severe thunderstorms that developed over South Central Wisconsin, producing hail up to 1 inch in diameter, merged into several squall lines that produced damaging wind gusts as they moved east through Southeast Wisconsin during the afternoon and evening hours of May 30th. Overall forcing for ascent over the region was provided by differential vorticity advection ahead of a progressive 500 mb negatively-tilted trough, with the storms developing on the nose of a moderate to strong low-level jet ahead of the wave. Moderate instability, reflected in mixed-layer CAPE values of 1000 to 1200 J/kg, and favorable wind shear contributed to conditions that produced broken bands of thunderstorms with damaging wind gusts and downbursts.

Source: NOAA Storm Events Database · episode 74801

Every report, in the Weather Service's words

Where It Hit

Location County Hazard Size Report
Beaver Dam Arpt (2.29 NW) Dodge Wind 70 mph wind The Dodge County Emergency Manager reported the roof of a barn was blown off, and trees in a cemetery on County Highway G downed by thunderstorm wind gusts estimated at 70 mph (61 knots) along a path from about 2 miles west of Beaver Dam into Beaver Dam.
Mayville Dodge Wind 70 mph wind Law enforcement officials reported a few trees and power lines downed by thunderstorm wind gusts estimated at 70 mph (61 knots) along a path from Mayville to Brownsville.
Delavan Walworth Wind 70 mph wind Law enforcement officials reported 20 buildings were damaged and around 40 trees and numerous power lines downed by a thunderstorm microburst with wind gusts estimated at 70 mph (61 knots) along a 2 mile-long, 1/4 to 1/2 mile-wide path through the City of Delavan.
Middleton Dane Wind 64 mph wind Madison TV 27 reported numerous trees and power lines blown down by thunderstorm wind gusts estimated at 65 mph (56 knots) in Middleton. Some cars were damaged by the downed trees, as well as a tree piercing the roof of a condominium. A shed was also destroyed by the damaging thunderstorm wind gusts.
Cottage Grove (3 W) Dane Wind 64 mph wind The public reported trees and power lines downed by thunderstorm wind gusts estimated at 65 mph (56 knots) 3 miles west of Cottage Grove.
Hillpt Sauk Wind 64 mph wind Law enforcement officials reported trees blown down by thunderstorm wind gusts estimated at 65 mph (56 knots) in the Hill Point area.
Columbus (2 S) Columbia Wind 64 mph wind Law enforcement officials reported trees two feet in diameter blown down by thunderstorm wind gusts estimated at 65 mph (56 knots) along a path from 2 miles south of Columbus to Fall River.
Randolph (3 SE) Dodge Wind 64 mph wind Law enforcement officials reported trees downed by thunderstorm wind gusts estimated at 65 mph (56 knots) 3 miles southeast of Randolph.
(msn)truax Fld Madis (1.2 WNW) Dane Wind 64 mph wind A newspaper article reported 23 trees and numerous power-lines blown down by thunderstorm wind gusts estimated at 65 mph (56 knots) about 1 mile west-northwest of Dane County Regional Airport. Some cars and homes were also damaged by the downed trees.
Randolph Dodge Wind 64 mph wind Law enforcement officials reported trees downed by thunderstorm wind gusts estimated at 65 mph (56 knots) in Randolph.
Downtown Madison (7 SW) Dane Wind 60 mph wind A trained spotter reported several large tree branches in excess of 6 inches in diameter downed by thunderstorm wind gusts estimated at 60 mph (52 knots) 7 miles southwest of the State Capitol in Madison. A couple power-lines were snapped by the tree debris.
Token Creek Dane Hail 1" hail The public reported hail measured to 1 inch in diameter in Token Creek.
Source: NOAA Storm Events Database, Wisconsin

Service areas this storm touched