Chombueng Marathon
Race Day Weather
Warm temps, hydrate frequently
Runners will face a starting temperature of 72°F, rising to 81°F by race end, with humidity at 78% and a dew point of 67°F. Wind will be light throughout, maxing at 5 mph. Given the conditions, hydration is essential, and runners should consider starting conservatively to manage heat.
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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.
