Historically, Chicago is approaching the coldest time of the year with the city’s average temperature bottoming out at 23 degrees from January 17-20.
Over the years during this period temperatures have dropped below minus 20 on several occasions and in 1985 Chicago recorded its all-time lowest temperature of 27 below on January 20.
This year will be totally different as exceptionally mild weather prevails. Following Sunday’s high in the middle 30s and a wintry mix early Monday, the mild weather will move in as the mercury reaches the lower 40s late in the day, then climbs to the middle 40 Tuesday.
A brief fallback will drop readings to the lower 40s Wednesday, but then a storm system in the Plains will deliver three cloudy and windy 50-degree days Thursday through Saturday that could even bring some rare January thunderstorms.