Boulderthon 5K
Boulderthon 5K 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 5K
The Boulderthon Heart to Heart 5K is a 3.1 mile out-and-back on the paved roads of east Boulder. It starts at 18th and Pearl Street, runs east along Pearl Street, and returns to finish in downtown near the Pearl Street Mall. The course is mostly flat with a gradual rise on the way back, at about 5,300 feet of elevation.
