SEVERE WEATHER UPDATE: The severe thunderstorm watch that had been issued for Stephenson, Jo Daviess, Winnebago, Boone and McHenry counties has been canceled, as well as for Green, Rock and Walworth counties. It continues for Carroll, Whiteside, Lee, Ogle and DeKalb counties until 9am Thursday.
A SEVERE THUNDERSTORM WATCH has been issued for most of the state of Wisconsin, including the counties of Green, Rock and Walworth until 2am Thursday. This watch has also been labeled as a ‘PDS’ Severe Thunderstorm Watch; Particularly Dangerous Situation, meaning the risk of extremely high wind, large hail and isolated tornadoes are particularly high with any thunderstorms that develop.
Thunderstorms have developed over northern Wisconsin Wednesday evening, quickly turning severe with numerous severe thunderstorm warnings extending from south of Rhinelander, WI to near Rice Lake, WI. These thunderstorms are expected to quickly increase in coverage over the next hour or two, growing into a rather large storm complex/cluster of storms, possibly a derecho, rapidly moving to the southeast towards south-central and southeast Wisconsin. Isolated tornadoes are possible with these storms, as well as widespread wind damage and large hail. Wind gusts could reach 90 mph locally.
The timeline for the storms to reach southern Wisconsin, possibly northern Illinois, appears to be near Midnight (a little sooner north), through roughly 4am Thursday. While a watch has not been issued for northern Illinois, it’s possible that one may be needed once storms grow and begin moving south. Be sure to have a way to receive watches and/or warnings through the night as the storms move closer.