Blue Sky Marathon
Race Day Weather
Cold start, warm finish ahead
Runners will face a cool start at 35°F, gradually warming to 56°F by the finish. With light winds at 6 mph and low humidity at 44%, conditions will be comfortable, but temperatures will rise significantly on later laps. Runners should start conservatively and adjust hydration frequency as temperatures climb, especially during the later stages of the race.
Pace Calculator
Get forecast alerts for Blue Sky Marathon
We'll text or email you when the forecast shifts — so you can adjust gear, pacing, and strategy. Max one per day.
Race Info
The Blue Sky Marathon is a 26.7-mile trail race in Fort Collins, Colorado, run on dirt trails between Horsetooth Mountain Park and Devil's Backbone Open Space along the Front Range foothills. The course has about 3,500 feet of elevation gain and loss, mostly singletrack with sections of rocky terrain and dirt road. First run in 2008, it is organized by Gnar Runners, which bills it as Fort Collins' original and only trail marathon. A half marathon (13.4 miles, 1,800 feet of gain) runs the following day over a shorter loop of the same terrain.
