Chombueng Marathon
Race Day Weather
Warm start, humidity high
Runners will face a starting temperature of 73°F, rising to 81°F by race end. With an average humidity of 76%, hydration will be crucial throughout. Wind will be light and variable, making it a non-factor. Runners should consider adjusting their pace conservatively to manage the heat and humidity.
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Race Info
The Chombueng Marathon is one of Thailand's longest-running marathons and a Boston Marathon qualifier, held in Chom Bueng, Ratchaburi Province, starting and finishing at Muban Chom Bueng Rajabhat University. It is a full member race of the Association of International Marathons and Distance Races, held annually on the third Sunday of January. The marathon starts at 3:00 AM to beat the heat, with a half marathon at 5:00 AM and a 10K mini marathon at 6:00 AM the same morning. The rural course is often described as flat, but its steady elevation gain over the full distance makes it more demanding than its reputation suggests.
