Boulderthon Half Marathon
Boulderthon Half Marathon race day weather
Comfortable temps, big temp swing
Mild 50°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 Half Marathon
The Boulderthon Half Marathon runs 13.1 miles through Boulder, Colorado, starting at 19th and Pearl Street. The route heads east along Pearl Parkway to Valmont Road, turns north on 61st and 63rd Streets to Jay Road, then comes back south and west on 57th Street and Independence Road. It returns to downtown by the 4 Mile Creek Trail and Folsom Street and finishes at 16th and Spruce Streets. The course is on paved roads and paved paths at about 5,300 feet of elevation, with roughly 385 feet of total climbing.
