www.chicagotribune.com/news/asktomwhy/ct-wea-1022-asktom-20111022,0,7408937.story

Chicago Weather Center

Ask Tom why: What is the latest date for an 80-degree day in Chicago?

October 22, 2011

Advertisement

Dear Tom,

What is the latest date that we have had an 80-degree day?

—Todd Wolfson, Chicago

Dear Todd,

A number of hardy Chicagoans anxiously anticipate the bluster, snow and cold of winter, but there are much more who, if given the choice, would opt for the sunny warmth of summer. And probably no day is as reminiscent of summer as an 80-degree day in late autumn.

On average, Chicago experiences its last 80-degree day on Oct. 9, but it has occurred as late as Nov. 1. On Nov. 1, 1950, Chicago's temperature jumped to 81 degrees, the third consecutive day of 80-plus temperatures — all record highs that still stand. Then the bottom fell out. The high the next day (Nov. 2) was 47 and traces of snow were observed on Nov. 3 and 4. Subzero readings occurred three weeks later, and that winter brought 54 inches of snow.