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

July 10, 2008: Straight-line wind and a tornado across seven counties

90mph
Strongest gust
1
Tornado
11
NWS reports

What the National Weather Service recorded

Two rounds of severe weather affected south-central and southeast Wisconsin on July 10th. An initial cluster of storms north of the Milwaukee area in Ozaukee County pulsed to severe limits and generated large hail up to 3/4 inch in diameter during the early afternoon hours. A second round of severe weather was associated with several clusters or short bowing segments of lines of storms that moved west to east across southern Wisconsin during the late afternoon and evening hours. Surface temperatures in the 80s and surface dewpoints in the 60s resulted in CAPE values of 1500 to 2000 while a vorticiy maxima at 500 MB moved across Wisconsin. Veering winds allowed for the development of rotating updrafts in a couple cells that generated two weak tornadoes. Otherwise, the severe weather type was powerful downburst winds.

Source: NOAA Storm Events Database · episode 20128

Every report, in the Weather Service's words

Where It Hit

Location County Hazard Size Report
Mc Farland Dane Wind 90 mph wind Powerful thunderstorm wind gusts toppled large trees and broke branches that brought down some power-lines. In McFarland, a house was blown down, and tree debris damaged a restaurant .
Darien Walworth Wind 75 mph wind Powerful thunderstorm wind gusts toppled several large trees and broke branches that brought down some power-lines. At least 6 homes sustained damage due to tree debris in the Walworth to Williams Bay area.
La Valle Sauk Wind 64 mph wind Powerful thunderstorm wind gusts toppled large trees and broke branches that brought down some power-lines.
Johnson Creek Jefferson Wind 64 mph wind Powerful thunderstorm wind gusts toppled several large trees and broke branches that brought down some power-lines. Five tents were damaged at the Jefferson County Fairgrounds.
Beaver Dam Dodge Wind 64 mph wind Powerful thunderstorm wind gusts toppled several large trees and broke branches that brought down some power-lines.
Whitewater Walworth Wind 64 mph wind Powerful thunderstorm wind gusts toppled several large trees and broke branches that brought down some power-lines.
Eagle Waukesha Wind 64 mph wind Powerful thunderstorm wind gusts toppled several large trees and broke branches that brought down some power-lines.
Portage (5 SW) Columbia Wind 64 mph wind Powerful thunderstorm wind gusts toppled several large trees and broke branches that brought down some power-lines.
Cross Plains Dane Wind 64 mph wind Powerful thunderstorm wind gusts toppled several large trees and broke branches that brought down some power-lines.
Sullivan (3.8 SSE) Jefferson Wind 58 mph wind Powerful thunderstorm wind gust measured at NWS office.
Waupun Arpt (2.82 WSW) Dodge Tornado EF1 This weak tornado uprooted 9 large oak trees and damage a barn roof. It spun up just northeast of the intersection of CTH W and CTH F and moved east-northeast across STH 68 near a bend in STH 68, and dissipated just southeast of the intersection of STH 68 and Buckhorn Road. The starting and end lat/long pairs of numbers are: 43.60684/-88.82342 and 43.61147/-88.80410. DI#27 (TH), DOD3. The winds were estimated at 94 mph. The average path width was about 30 yards.
Source: NOAA Storm Events Database, Wisconsin

Service areas this storm touched