Chicago Marathon
Race Day Weather
Comfortable temps, moderate wind
Mild 57°F temps at gun time mean comfortable early miles without overheating risk. Moderate winds around 14mph may affect pacing on open sections of the course. Moderate humidity at 71% is worth noting for effort level, especially in later miles.
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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.
