Last weekend’s outbreak of killer tornadoes in southwest Indiana was a tragic reminder that portions of the central and southern Midwest and the South experience a secondary peak of severe weather in late fall. November is a time of year when strong low pressure systems traverse the nation, fueled by strengthening jet streams and head-on clashes between the season’s first intrusions of arctic cold and the last northward surges of summer’s heat and humidity. November tornadoes are the warm-side product of the same storms that produce early season blizzards in the northern Plains, and the hurricane-force winds and monster-sized waves on the Great Lakes on their cold flank (like the one responsible for the sinking of the Edmund Fitzgerald on Nov. 10, 1975).
Sources: NWS archives; Storm Prediction Center; “Significant Tornadoes,” Thomas P. Grazulis; and Frank Wachowski
WGN-TV/Steve Kahn
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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.
