Hail in Wisconsin, May 12, 2000

Probably the costliest southern Wisconsin hailstorm in the past 100 years struck the northern parts of Marquette and Green Lake Counties during the mid to late morning hours. This was the third round of severe thunderstorms to strike southern Wisconsin due to the same basic weather pattern. Hailstones the size of baseballs (up to 3 inches in diameter) pounded the northern 3 mile stretch of these two counties, resulting in substantial damage to hundreds of homes (roofs and siding) and hundreds of vehicles. Two people in Marquette County and 4 people in Green Lake County were injured by the large hailstones and needed medical treatment. The hailstones left impact marks on sidewalks in the Crystal Lake area of north-central Marched County. In Green Lake County crop damage was also noted. Downburst winds of 60 to 70 mph also accompanied the hail, resulting in many trees being pushed over. Interestingly, this severe hailstorm occurred north of a warm front, with air temperatures only in the 60s. The warm front moved north to a Wisconsin Dells to Sheboygan line while a frontal "triple-point" formed near the Dells due to a cool front pushing in from the west. The thunderstorm which first produced hail in Sauk County while moving northeast, gradually turned more to the right (east), as it entered Marquette, Green Lake, and Waushara Counties, and transformed into a high-precipitation supercell. Eventually this supercell did spawn a tornado in Manitowoc County, and 100 mph straight-line winds in Calumet and Manitowoc Counties.