December has historically hosted the third fewest 50° highs of any month. But, that didn’t stop the mercury Tuesday from peaking at 50° and 52° highs at O’Hare and Midway respectively, the area’s warmest readings in two weeks. As a signal the mild air isn’t done yet, Chicago’s predicted highs over the coming 7 days will average 20° milder than the daily highs observed the opening week of December, just the opposite of what might be expected.
Thunderstorms developed in southern counties of the metro area Tuesday afternoon with cloud tops above 40,000 ft. The first cloud-to-ground lightning stroke detected in northeast Illinois occurred around 4:07 p.m. well SW of Chicago in Livingston County. Storms spread northeastward in the two hours which followed generating as many as 40-50 lightning discharges per 15 minutes as they moved over sections of Kankakee and Will Counties and into northern Indiana.
--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.
