San Antonio Half Marathon
Race Day Weather
Cool start — fast day potential, big temp swing
A cool 49°F at the start line is ideal for fast times — expect to warm up quickly once you're moving. Temps will climb significantly to 64°F by later miles, so expect fading conditions as the race progresses. Light winds shouldn't be a major factor for pacing. Moderate humidity at 67% is worth noting for effort level, especially in later miles.
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Race Info
The San Antonio Half Marathon starts and finishes at Hemisfair in downtown San Antonio. The course heads through the Southtown and King William neighborhoods, then north through the central business district past Travis Park and the Alamo before returning downtown to the finish. It is run on the Sunday of race weekend and is USATF-certified.
