Flash Flood — Kenosha, Wisconsin

2009-06-19 · near Downtown Kenosha, Kenosha, Wisconsin

Event narrative

Heavy rains resluted in flash flooding in the southeast part of Kenosha County. Numerous streets were flooded with water depths of 2 to 4 feet , and several were impassable. Several vehicles were stranded in the flood waters and rescues were performed. Water depths were up to the windows of cars in the city of Kenosha. Interstate 94 at STH 165 was covered by water and southbound lanes were closed. STH 50 was closed from Intestate 94 east to CTH H. CTH C was closed going west from Interstate 94 due to high water levels. Several other roads were closed. Damage was noted to several culverts and road shoulders, and water lift stations/pumps were damaged in some facilities. Compounding the flooding problem was the loss of electrical service which meant sump pumps in homes didn't operate. Basement flooding was a major issue. WSR-88D Doppler radar rainfall estimates on top of a wet ground were on the order of 3 to 6 inches for a 24-hour period ending 2000 CST. Some farm fields were probably flooded, per newspaper articles, but no direct loss estimates were available. Therefore, a nominal $200K was estimated for the purpose of this documentation.

The initial Uniform Disaster Situation Report compiled by the Kenosha County Emergency Management indicated at at least 600 homes were affected by flood waters, but had no damage, at least 590 homes had minor flood damage, at least 11 homes had major damage, and at least 1 home was destroyed, for a monetary loss of at least $11,975,000. At least one business had major flood damage for a monetary loss of at least $310,000. Total estimated private sector damage was at least $12,285,000. Public sector damage inlcuded about $265,000 to road systems, $110,000 damage to water control facilities, $18,000 damage to public buildings & related equipment, and about $295,000 to public utility systems, for a total public sector damage estimate of about $683,000. Additionally, debris clearance cost about $22,000, protective measures cost about $57,000, and there was other $91,000 in miscellaneous costs. These last three values are not considered direct property damage.

Wider weather episode

The final in a series of upper level disturbances propagated northeastward across southern Wisconsin during the afternoon and evening of June 19th. This impulse, combined with strong upper level jet dynamics and a very moist, unstable atmosphere, allowed for storms to redevelop across southern Wisconsin. Bulk shear values of 50-60 kts, MLCAPE values near 2500 J/kg, and PW values near 1.8 allowed for a series of short thunderstorm lines to move through southern Wisconsin. The result was wind damage, a tornado in Kenosha County, and widespread flash flooding. Due to the heavy rainfall from earlier storms, some locations received 3 to almost 7 inches of rain in less than 24 hours. Flash flooding occured in Kenosha, Walworth, Waukesha, Milwaukee, and Racine counties.

View location on OpenStreetMap → (42.6090, -87.8300)

Source: NOAA Storm Events Database, event_id 176860. Narrative written by the NWS forecast office that issued the report.