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Flash Flood — Waukesha, WI

Jun 21, 2011

A warm front lifted into southern Wisconsin ahead of slow-moving low pressure in Iowa. Moderate wind shear with 0-6km shear values of 35 to 45 knots and mixed layer (ML) CAPE in the 1500 to 2500J/kg range in place over the region combined with enhanced lift from an upper disturbance rotating through the base of an approaching upper trough to produce strong to severe supercell thunderstorms during the afternoon into the evening of June 21st. The storms produced two EF1 tornadoes in the vicinity o

Source: NOAA National Weather Service Storm Events Database (event 327543). Narrative written by NWS staff at the time of the event.

Flood Risk Context for Waukesha, WI

This event is one of many recorded floods in Waukesha County. See the full FEMA flood zone map, NFIP claim totals, and disaster history for the area.

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