Chicago appears headed into rare temperature territory Thursday—at least by November standards. Should a predicted high of 72° verify, it would mark only the 84th time the mercury here has passed 70° beyond Nov. 3 in 135 years of official weather records. Put a bit differently, fewer than one half of 1% of Chicago’s high temperatures this late in the season have been as warm.
Exceptionally strong westerly jet stream winds are whisking Pacific air across the country. The already mild air warms further as it sinks out of the Rockies and into the Plains, a process which induces compressional warming—raising its temperature.
The coming warmth is in marked contrast to the record chill recorded here in early November 1991. That early season cold spell produced six new temperature records and a string of eight consecutive days below 40°.
WGN-TV Chief Meteorologist Tom Skilling and the WGN Weather Center staff provide daily coverage of weather in the Chicago area.
