Dear Tom,
In August, O’Hare recorded 13 thunderstorm days. What is the record for the most thunderstorm days in a month here? Thomas Peterson,Mount Prospect
Dear Thomas,
Chicago weather historian Frank Wachowski says that while last August’s 13 days with thunderstorms was certainly substantial and more than double the month’s long-term average of six, May 1944 takes the top prize for the most thunderstorms days here with 15, followed by the Mays of 1902 and 1912 and June 1934–all with 14.
In a typical year, Chicago averages about 38 days when thunderstorms occur, though in 1975 the city recorded 66 such days, the greatest number on record. In contrast, the city’s year with the least number of thunderstorm days dates back more than a century to 1875, with five.
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Tom Skilling is chief meteorologist at WGN-TV. His forecasts can be seen Monday through Friday on WGN-TV News at noon and 9 p.m.
WGN-TV meteorologists Steve Kahn, Richard Koeneman and Paul Dailey plus weather producer Bill Snyder contribute to this page.
