Temperatures were in free fall late Thursday, predicted to bottom out in the 30s across cooler sections of the Chicago metro area early Friday—the lowest readings here since the 36° low nearly a month ago on April 17. Temps that low at such a late date are rare. Only 36 of the 8,086 sub-39° low temperatures on record at Midway Airport over the past 79 years have occurred between May 18 and the arrival of warm summer weather. That’s just 4/10ths of a percent of all low temps on the books since 1929.
Dew points become an invaluable aid in predicting low temperatures in this sort of pattern. That’s because overnight temperatures often tumble toward the dew point when skies are clear, winds are light and the air is exceptionally dry.
North Woods residents in upstate Wisconsin and Minnesota really shivered Thursday morning. Lows dropped to 23° at Land O’Lakes Wisc. and 27° at Hibbing and International Falls, Minn.
-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.
