Hail — Washington, Wisconsin

2012-08-07 · near Kewaskum, Washington, Wisconsin

Event narrative

A trained spotter reported large hail, between 1 1/4 inch and 1 1/2 inch in diameter that fell in Kewaskum. The 5-8 minute hail storm was the worst to hit Kewaskum in many years. Roughly 200 vehicles suffered damage from the hail, as well as many homes, condos, apartments and outdoor equipment. Hail damage to vehicles was about $250,000, and about $1.75 M to buildings and equipment. This information was supplied by local auto-body shops and insurance companies and is a broad estimate.

Wider weather episode

A cold front...moving into a hot, unstable air mass over southeastern Wisconsin produced scattered strong to severe thunderstorms during the late afternoon hours of August 7th. High temperatures rose to around 90 degrees, with dew point rising to the lower to middle 60s in eastern sections due to a lake breeze bringing in moisture off Lake Michigan. The lake breeze also enhanced low level convergence, aiding the overall forcing along the front for thunderstorm development. Surface-based CAPE values were between 2,000 and 3,000 J/kg, with steep mid-level lapse rates and sufficient bulk shear to support the sustained updrafts needed to produce large hail. The thunderstorms produced large hail up to 1.50 inch in diameter that damaged trees, vehicles, homes and outdoor equipment in Kewaskum in Washington County, with reports of smaller hail between 1/4 inch and 3/4 inch in Fond Du Lac and Dodge counties.

View location on OpenStreetMap → (43.5200, -88.2200)

Source: NOAA Storm Events Database, event_id 407773. Narrative written by the NWS forecast office that issued the report.