How likely is it that we will drop below zero the rest of this winter?

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Dear Tom,
How likely is it that we will drop below zero the rest of this winter?
Don Dodge, Lake Station, Indiana
 
Dear Don,
February 4 marked the peak of Chicago’s subzero occurrences registering below zero temperatures 24 times since 1871, more than another other day of the year. Runner-up is January 28 with 22 occurrences, followed by nine days logging 20 or 21 in the January 5-February 9 period. With lengthening daylight and higher sun angle the subzero threat drops off sharply by mid-February, historically ending with the city’s latest subzero of minus 1 on March 22, 1888. While subzero weather is still possible this season, snow cover, one of the prime ingredients for generating subzero cold has been noticeably lacking. If we don’t get a decent snow cover in the next couple of weeks, the city might just escape additional subzero weather for the remainder of this season.