Not since 2001 have the opening nine days of May been milder across the Chicago area. Tuesday’s predicted 73° high marks the 17th time in 2006 a daytime high has surged past 70°—nearly 1.5 times the long-term average by this date since 1871. May, 2006’s average of 57.1° exceeds the area’s 135 year long-term average by 2.1°.
The temperature downturn predicted to begin Thursday threatens to produce an extended series of daytime 50s. The average date of the Chicago area’s last three-day string of 50s has been May 1-3 at the city’s South Side Midway Airport observation site—making the predicted cool spell later this week fairly impressive by historical standards. Any sunshine through breaks in the clouds could produce localized heating, forcing temperatures out of the 50s. The city’s latest three-day string of 50s occurred June 4, 5 and 6, 1928 when readings peaked at 59, 54 and 58°.
-Tom Skilling
WGN-TV Chief Meteorologist Tom Skilling and the WGN Weather Center staff provide daily coverage of weather in the Chicago area.
