City of Trees Marathon
Race Day Weather
Cool start — fast day potential, big temp swing
A cool 49°F at the start line is ideal for fast times — expect to warm up quickly once you're moving. Temps will climb significantly to 66°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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Race Info
The City of Trees Marathon is held each October in Boise, Idaho, with a marathon, half marathon, 10K and 5K. The courses use the Boise Greenbelt, and in 2026 the start and finish were at Boise State University Stadium. The race is organized by the Boise nonprofit SoleKIDs and has a 6-hour marathon limit.
