While Tuesday was a warm one -- and a record-breaker -- it didn't set an new all-time high for January.
Warm, moist air from the south marched into the Chicago area late Monday night, pushing the mercury at O'Hare International Airport to 59 degrees even before sunrise. That tied the previous record this date set back in 1914.
But another record, the all-time high temperature for the month, will stand. Weather records show the temperature reached 67 degrees on Jan. 25, 1960. Tuesday's temperature at O'Hare reached 63 degrees before dropping again.
How rare is 60 degrees in January in Chicago? It has only happened 33 times in the past 141 years. The last time it was this warm was on Jan. 7, 2008, when temperatures reached 65 degrees and an isolated tornado was spotted in the northwest suburbs.
The warmth didn't come without warnings, though. Dense fog throughout the area made driving and air travel difficult early in the day, and heavy rainfall was expected to continue into the evening hours. The area could see an unseasonable one to three inches of rain Tuesday night.
The problem? The ground is frozen, and that could mean some flooding issues. The National Weather Service on Monday issued flood watches for portions of Illinois and Indiana, including Cook, Ford, Grundy, Iroquois, Kankakee, Livingston and Will counties in Illinois, and Benton, Jasper, Lake, Newton and Porter counties in Indiana.
By Wednesday, warmth won't be the word to describe the weather. Falling temperatures will create a rain/snow mix. The mercury is expected to reach a more winter-like 18 degrees by Thursday.