Chicago’s mildest temperatures since the 60° high here nearly two weeks ago on Nov. 29 may lend support Tuesday to rare December thunderstorm development. Only one of the metro area’s 38 yearly t-storms occurs this month on average—just 3% of the city’s annual total. While it’s hardly a certainty all sections of the metro area will experience thundery downpours, odds for thunderstorms appear highest in the south and east suburbs. The day’s impressive vertical temperature decline—a situation meteorologists refer to as an “unstable” atmosphere—in combination with the arrival of a powerful pocket of upper level winds, supports the potential for t-storms similar to those in the Omaha, Nebraska area where 3/4” hail bombarded Falls City Monday. It’s been four years since December thunderstorms traversed the area on the 18th and 19th of this month in 2002.
--By Tom Skilling, WGN-TV Chief Meteorologist
WGN-TV Chief Meteorologist Tom Skilling and the WGN Weather Center staff provide daily coverage of weather in the Chicago area.
