Founders Half Marathon
Race Day Weather
Cool morning, steady conditions
Runners will face a temperature rise from 35°F to 47°F throughout the race. Wind will be light at 6 mph, with gusts up to 15 mph, posing minimal impact. With humidity at 57% and a slight chance of light rain, runners should dress in layers and maintain hydration, adjusting pace as needed for the warming trend.
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Race Info
The Founders Half Marathon is a 13.1-mile out-and-back race in Potomac, Maryland, organized by the DC Road Runners Club. The course runs along the C&O Canal Towpath from the Carderock Recreation Area, with two water stops at Lock 10 and Lock 6 passed twice each. It is race #2 of DCRRC's winter Snowball Series and was known as the Gar Williams Half Marathon before 2025, named for a past president of the club and of the Road Runners Club of America.
