Chicago hasn’t had a 12”+ snowstorm this early per official Chicago records. Of course it remains to be seen if they’ll get 12” officially. The official forecast is for 8-12”, which is difficult to achieve and historic enough, especially for lake effect!
The records have been at the well inland O’Hare Airport since 1980 and were at the not as inland Midway Airport 1942-79. Prior to that they were closer to the lake.
Keeping this in mind: the official Chicago record heaviest Nov snowfall for a single storm is 12.0” (11/25-6 of 1895), then 11.2” (11/20-1 of 2015), and then 9.3” (11/6-7 of 1951):
THE FOLLOWING IS THE UPDATED LIST OF THE LARGEST SNOW EVENTS
DURING THE MONTH OF NOVEMBER FOR CHICAGO DURING THE PERIOD OF
RECORD...WHICH IS SINCE 1884:
RANK DATES EVENT SNOWFALL /IN/
-----------------------------------------
1. NOV 25-26 1895 12.0
2. NOV 20-21 2015 11.2
3. NOV 6-7 1951 9.3
4. NOV 26-27 1975 8.6
5. NOV 27-28 1891 6.0
RANK MONTH MONTHLY SNOWFALL /IN/
-----------------------------------------
1. NOV 1940 14.8
2. NOV 1895 14.5
3. NOV 1951 14.3
4. NOV 2015* 11.2
5. NOV 1975 10.8
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