Storm Record · Walworth County
May 20, 2012: Straight-line wind in Walworth County
What the National Weather Service recorded
Scattered thunderstorms developed ahead of a cold front, trailing from low pressure that moved from west central Wisconsin into western Ontario during the day on May 20th. One cluster of thunderstorms pulsed up to severe levels, producing damaging wind gusts over Walworth County that downed power lines and trees. Surface temperatures in the 80s and dew points around 60 degrees produced mixed-layer CAPE values around 1500 J/kg. Forcing with surface convergence along the front was aided by lift attributed to differential positive vorticity advection as an upper level shortwave lifted across western Wisconsin.
Source: NOAA Storm Events Database · episode 64378
Every report, in the Weather Service's words
Where It Hit
| Location | County | Hazard | Size | Report |
|---|---|---|---|---|
| Pell Lake | Walworth | Wind | 64 mph wind | The Walworth County Emergency Manager reported numerous trees and power lines downed by thunderstorm wind gusts estimated at 65 mph (56 knots) in a swath from Bloomington Township, near Pell Lake, to Lyons. |