On only six occasions in recorded history has Chicago experienced a temperature below -18°C in March.Tonight could be the 7th:
A sub-0 reading at O’Hare by daybreak Thursday would be the latest a low temp has dropped below 0 [Fahrenheit] here in the 33 years—–since 1982. The -19°C reading being predicted is hardly a common occurrence so late in a cold season. In fact, of Chicago’s 1,041 sub-0 readings in 144 years of official temp records, only 6 have occurred beyond March 5th (Thursday’s date). And on a broader scale, only 12 of the 144 Marches on the books since official records began here in 1871 have managed one or more sub-zero temps.
Daytime highs could register as much as 28°C warmer in a week
What’s to happen in the wake of the frigid late-season chill of the next two days is the most significant pattern change across North America since December. Major warming is projected. The pace of the warming will depend on the speed with which snow melts and on wind direction, since any “easterly” winds at this time of year deliver a very chilly brand of air off ice-cluttered Lake Michigan.
Oh, and we've had snow on the ground now for 34 days straight, which isn't a record but is unusual this late in the year. It's not the snow on the ground I find objectionable, either; it's having to keep a pair of shoes at the office and clomping to work wearing boots every day. I hope next week's warm-up finishes that phase of the year.