The Big Half
Race Day Weather
Comfortable temps, warming through the race
Mild 58°F temps at gun time mean comfortable early miles without overheating risk. Temperatures rising to 68°F through the course will gradually increase perceived effort in the second half. Light winds shouldn't be a major factor for pacing. Moderate humidity at 76% is worth noting for effort level, especially in later miles.
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Race Info
The Big Half is a half marathon through central and southeast London, organized by London Marathon Events, the team behind the TCS London Marathon. First held in 2018, the race starts on The Highway near the north side of Tower Bridge, loops east through Limehouse toward Canary Wharf, then crosses Tower Bridge and runs through Bermondsey, Rotherhithe, and Deptford to finish beside the Cutty Sark in Greenwich. The half is the centerpiece of a community-focused race day that also includes the one-mile Big Mile fun run and the New Balance Big Relay team event.
