Blue Sky Marathon

Fort Collins, CO, USA · October 17, 2026
partly-cloudy-day43°·68° high·Breezy·Dry
9
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Race Day Weather

partly-cloudy-day
43°at start
68° high
Breezy
Dry

Cool start, warming finish

Runners will face a cool start at 43°F, maintaining this temperature until reaching the higher elevation at mile 4. As they descend back to the finish, the temperature will rise to 61°F, creating a warmer finish. With light wind at 8 mph, runners should focus on pacing conservatively in the early laps and prepare for the warmer conditions of the later laps, ensuring adequate hydration.

Race day forecast available in 4 days
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Pace Calculator

Distance: 26.2mi
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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.

FAQ

When is the 2026 Blue Sky Marathon?

The 2026 Blue Sky Marathon will be held on Saturday October 17, 2026.

Is the Blue Sky Marathon a Boston Marathon Qualifier?

No, the Blue Sky Marathon is NOT a Boston Marathon qualifier.

What is the time limit for the Blue Sky Marathon?

The time limit for the Blue Sky Marathon is 9 hours.

What will the weather be like for the 2026 Blue Sky Marathon?

The forecast calls for a high of 69°F and a low of 41°F with a 3% chance of rain.

What is the elevation profile of the Blue Sky Marathon?

The Blue Sky Marathon has 3500ft of total elevation gain. View the interactive course map above for a detailed elevation profile.

Historical Weather

Based on 18 years of data
Avg Temp
64°F
L:41° H:65°
RunScore
8
Conditions
Rain Freq
6%
1 of 18 yrs
Wind10mph
Dew30°F

Temperature History

Range of temperatures during race hours for each year.

Detailed History

YearConditionsLow / HighRainScoreResults
2025
clear-night
42°/59°-
8
2024
cloudy
43°/60°-
9
2023
clear-night
44°/79°-
8
2022
clear-night
43°/65°-
8
2021
clear-night
28°/70°-
8
2020
clear-night
38°/45°-
7
2019
clear-night
35°/65°-
8
2018
clear-night
37°/70°-
8
2017
clear-night
43°/53°-
6
2016
clear-day
51°/81°-
8
2015
cloudy
49°/54°-
9
2014
clear-night
46°/75°-
8
2013
clear-night
38°/67°-
8
2012
partly-cloudy-night
24°/55°-
8
2011
clear-day
50°/84°-
8
2010
clear-day
41°/77°-
8
2009
partly-cloudy-night
39°/46°Light
7
2008
partly-cloudy-night
48°/70°-
9