National Weather Service
A radar composite shows total precipitation so far over Wisconsin and neighborhing states during the recent storms.
After several months of near-drought conditions in south-central Wisconsin, a spate of showers and thunderstorms have socked the region over the last two weekends. Round one consisted of an epic lightning storm in the early morning hours of Monday, Aug. 13, one in which strikes started fires in Fitchburg and Madison, including on the roof of J.H. Findorff & Son construction headquarters next to Monona Bay. Round two, meanwhile, is ongoing, and it's turning out to be much more destructive.
Over the weekend of Aug. 18-19, steady showers doused most of southern Wisconsin, with rainfall amounts well in excess of six inches in the southwest corner of the state. As described in a report provided by the National Weather Service:
Copious amounts of rain fell as several storms repeatedly moved throught the same areas. The axis of maximum rainfall amounts stretched from La Crosse through Richland County into Sauk and northern Iowa County into Dane County onto southern Jefferson to Racine County.
Many roads were reported to be covered with water Saturday night, and some roads were closed. There were reports of bridge washouts or damage to bridges in Dane and Sauk counties. Several rivers and streams rose to bankfull levels or even flood stage.
WSR-88D Doppler rainfall estimates were in an excess of 10 inches in parts of Crawford and Richland Counties, 10 to 12 inches in southwestern Sauk, northwestern Dane, and in a couple spots in southern Dane County. Up to 6 to 10 inches was indicated over most of the remainder of south central Wisconsin, and 3 to 6 inches over southeast Wisconsin.
Due to these conditions, Wisconsin Governor Jim Doyle declared a State of Emergency on Sunday afternoon, an action "authorizing activation of the Wisconsin National Guard, ordering the Wisconsin Emergency Management (WEM) to lead the state's emergency response efforts, and directing all state agencies to assist with local communities as they recover from this natural disaster." More information about the ongoing situation is provided here by Wisconsin Emergency Management.
A video clip of the Aug. 13 lightning storm follows below, along with several others from that storm and this past weekend's flooding.
There are two other clips online featuring the lightning storm a week ago (here and here), both of which were shot by UW student Stephen Dorshorst. More videos are also being published that feature the results of this weekend's rainstorms, including one that shows a swollen pond just off Old Middleton Road on the west side and another that tours a flooded basement.
Any respite is unlikely over the next few days. Several more rounds of heavy rains are forecast for southern Wisconsin through the rest of the week, with a possibility of two to five or more inches through Friday. "With the ground already fully saturated and many rivers above flood or bankfull stage," notes a forecast from the NWS, "additional flooding is expected."