Boulderthon 10K
Boulderthon 10K race day weather
Comfortable temps, big temp swing
Mild 55°F temps at gun time mean comfortable early miles without overheating risk. Temps will climb significantly to 82°F by later miles, so expect fading conditions as the race progresses. Light winds shouldn't be a major factor for pacing.
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About the Boulderthon 10K
The Boulderthon 10K is a 6.2 mile road race through downtown Boulder and the flat east side of town. It starts at 19th and Pearl Street, follows Pearl Street and Pearl Parkway east toward Cottonwood Lake and returns the same way. The finish is on the Pearl Street Mall. The course is paved and mostly flat to gently rolling, at roughly 5,300 feet of elevation.