Boats were snapped from moorings, a semi-trailer was flipped and at least two cars of a freight train in Michigan City were blown off the tracks as the area’s most powerful summer thunderstorms began roaring ashore Wednesday evening. Hail the size of tennis balls crashed to earth in the stormy downpours which were delivered by wind gusts so powerful as to be almost off the charts here. A Great Lakes Environmental Research Laboratory anemometer (wind sensor) near the harbor in Michigan City clocked a gust of 106 m.p.h. at about the time (6:12 p.m.) a trained observer reported a tornado touchdown in the city. Only the rarest of the planet’s estimated 50,000 daily thunderstorms produce triple digit wind speeds. The report of a touchdown was bolstered by the presence a Tornado Vortex Signature (TVS) on the National Weather Service’s powerful Doppler Radar—an indication of an especially strong rotation.
-Tom Skilling WGN-TV Meteorologist
WGN-TV Chief Meteorologist Tom Skilling and the WGN Weather Center staff provide daily coverage of weather in the Chicago area.
