We are in the midst of a long hot spell. What are the most consecutive days of 90 degrees and above, and what was the hottest July on record?
Dear Tom and Mark,
Using the city’s official climate data, the longest run of 90-degree plus days is 11, reached in four years, all during the hot 1950s. They were- August 24-September 3, 1953, June 11-21, 1954, July 26-August 5, 1955 and August 19-29, 1959. Unofficially, the city recorded a 12-day stretch in 1936 at Midway Airport from July 6-17, that included an eight straight days of triple-digit heat from July 7-14. At that time, the city’s official thermometer at the University of Chicago, failed to reach 90 on several days, a result of persistent lake breezes. The city’s warmest July was in 1955, averaging 81.3 degrees and logging 19 90-degree-plus days.