Chicago Marathon
Race Day Weather
Cool conditions, strategic pacing required
Runners will face temperatures starting at 57°F and climbing to 59°F, with average humidity around 71%. Wind will be a factor with headwinds from miles 2-14 and varying crosswinds throughout. To maximize performance, runners should adjust their pace during the headwind segments and take advantage of the tailwind from miles 3-8 and 24-27.
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Race Info
The Chicago Marathon starts and finishes in Grant Park, looping through 29 Chicago neighborhoods and crossing the Chicago River six times. The flat, fast course is a Boston qualifier and has produced seven marathon world records, most recently Ruth Chepng'etich's 2:09:56 women's mark in 2024. It's one of the seven Abbott World Marathon Majors, held every year on the second Sunday of October.
