Hail and Damaging Winds in Michigan, May 17, 1999

An unusually warm day for mid-May in southeast Michigan, with temperatures near 90 degrees in many locations. The heat and humidity made the atmosphere very unstable, and allowed thunderstorms to develop in the afternoon. Several of the storms became severe during the late afternoon and evening hours.The first few severe storms of the day were in the Saginaw Bay area, and produced large hail. The largest hail (golfball sized) fell in Port Hope.As thunderstorm activity gradually migrated south, large hail reports became less frequent. The largest hail in the southern part of the area was quarter sized near Saline. However, these southern storms produced stronger wind gusts. The highest measured wind gusts were 54 mph at the University of Michigan in Ann Arbor, and 51 mph at the airport in Owosso. However, winds were estimated much higher in some locations. The highest estimated gusts were near 90 mph just east of Deckerville.The most common effect of the severe wind gusts was to down trees and power lines. Power lines were downed across Interstate 94 near Dexter, closing the freeway for a short while. A few agricultural outbuildings were destroyed just northwest of Oakley, just south of Sandusky, and east of Deckerville. Windows were blown out of a Marlette home, while a home in Northville lost a number of shingles. In Ortonville, the roof was torn off a dugout at a ball field, and a home had a falling tree go through its roof. A tree was felled onto a Sandusky home, heavily damaging a porch; just south of town, a mobile home was shifted off its foundation. East of Deckerville near Lake Huron, a travel trailer was moved by the wind.