Heading home from New York just now, and came across an infographic from today's Chicago Tribune about the weather in Chicago on this day in 1934. My heavens. After 21 days of 32°C-plus temperatures, Midway Airport hit 43°C on July 23rd, with the official temperature at University of Chicago hitting 41°C the next day—the hottest temperature officially recorded in Chicago history. (Lakeside temperatures were 9°C cooler than even a short distance inland.)
It's not quite that hot today, but it could be again in a few years. Regularly. But at least it won't be as bad for us as for the folks in the Southwest and Southeast.