Dear Tom,

As this snow season concludes I notice there is an 8.7 inch difference between O’Hare and Midway, when the normal difference is less than 1/2 inch. Has there ever been a larger difference?

—Bill Ginsberg, McHenry

Dear Bill,

Chicago climatologist Frank Wachowski checked the data for the 43 snow seasons since O’Hare has been official dating back the winter of 1979-80. In those 43 seasons, Midway has had more snow in 23 seasons, a little more than half. During those 43 seasons, the average difference between the two airports was 4.9 inches. The largest difference was 15.3 inches during the winter of 2000-01 when Midway out snowed O’Hare 54.5 inches to 39.2 inches. Runner-up was the 2009-10 season with O’Hare logging 10.3 more inches. This winter’s 8.7 inch difference ranks fourth, just ahead of a 10.0 difference in 1988-89.