Boulder Rez Marathon
Boulder, CO, USA · August 15, 2026
Race Day Weather
62°at start
88° high
Light
Dry
Comfortable temps, big temp swing
Starting at 62°F, heat will be a factor from the gun — go out conservative and stay on top of hydration. Temps will climb significantly to 88°F by later miles, so expect fading conditions as the race progresses. Light winds shouldn't be a major factor for pacing.
Race day forecast available in 49 days
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Distance: 26.2mi
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FAQ
When is the 2026 Boulder Rez Marathon?
The 2026 Boulder Rez Marathon will be held on Saturday August 15, 2026.
Is the Boulder Rez Marathon a Boston Marathon Qualifier?
Yes, the Boulder Rez Marathon is an official Boston Marathon qualifier.
What will the weather be like for the 2026 Boulder Rez Marathon?
The forecast calls for a high of 89°F and a low of 61°F with a 5% chance of rain. Check our detailed hourly forecast above for the best marathon race plan.
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