Chicago Marathon
Race Day Weather
Cool start, warm finish
Runners will face a temperature range from 58°F at the start to a warm 75°F by the finish. Humidity will average 68%, prompting a need for hydration and conservative pacing as temperatures rise. The first half features beneficial tailwinds, while miles 9-23 will introduce headwinds, making those stretches particularly challenging. Adjusting pace during the warmest segments and planning hydration breaks will be crucial for success.
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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.
