Dear Tom,

I remember a low of 32 degrees on Sept. 22, 1995. Is that our earliest freeze? How often have Chicago temperatures reached 32 degrees or lower in September?

—Willie Neuman, Batavia

Dear Willie,

Your memories are right on. Following a strong cold front, the mercury dropped to 32 degrees at O'Hare International Airport on Sept. 22, 1995, the city's earliest freeze on record. It was even colder the next morning when the low dropped to 29. Since records began in 1871 there have been just nine official September freezes here. Prior to 1942, because the official temperatures were taken close to the lake and strongly influenced by water temperatures still in the 60s, the city's lone September freeze was a 32 on Sept. 30, 1899. In 1942 when the official site was moved inland to Midway Airport, the city immediately logged three subfreezing days on Sept. 25, 27 and 28.