What is the latest date Chicago has ever had a snow cover?
David Sanders Chicago
In a typical winter, Chicago averages about 43 days, where the ground is covered with at least one inch of snow. Chicago weather historian Frank Wachowski checked the records and found that the average date of the last inch of snow cover occurs around March 20. Over the course of the city’s snow climatology, dating back to the winter of 1884-85, the latest date for one inch or more of snow cover was April 24, 1967, when three inches covered the ground. This snow was not the remnants of the January 26-27, 1967 23.0-inch snowfall, but the result of 3.1-inch snowfall on April 23, two days after deadly F-4 Oak Lawn tornado. The city did receive 2.2 inches of snow on May 1-2, 1940, but it quickly melted, and the official snow cover for both days is listed as a trace.