Champlain Islands Marathon

South Hero, VT, USA · October 18, 2026
partly-cloudy-day42°·54° high·Light·Dry
8
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Race Day Weather

partly-cloudy-day
42°at start
55° high
Light
Dry

Cool conditions, steady breeze

Runners will face a temperature increase from 42°F to 55°F, with an average humidity of 69% and a dew point of 39°F. Wind will come from the WSW at 8 mph, with gusts reaching up to 22 mph. Runners should maintain a consistent pace and consider hydration strategies, as conditions are favorable for racing.

Race day forecast available in 144 days
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Race Info

The certified (VT15301JK*) marathon and half-marathon begin and end near the house where Clarence H. DeMar, seven-time Boston Marathon Winner, once lived. The half-marathon course is out and back on the west shore of South Hero and Grand Isle; a land of farms, apple orchards, and summer cottages. The terrain is flat to rolling.

The entire course is paved. The full marathon course is two out-and-backs of the half-marathon course.

The time cut off for the marathon is 6 hours. The time cut off for the half-marathon is 4 hours.

*The certification is under the old race name, but applies to the new name as the course is unchanged. Formerly the Green Mountain Marathon.
Wikipedia

Area Map

Course Map

FAQ

When is the 2026 Champlain Islands Marathon?

The 2026 Champlain Islands Marathon will be held on Sunday October 18, 2026.

Is the Champlain Islands Marathon a Boston Marathon Qualifier?

Yes, the Champlain Islands Marathon is an official Boston Marathon qualifier.

What is the time limit for the Champlain Islands Marathon?

The time limit for the Champlain Islands Marathon is 6 hours.

What will the weather be like for the 2026 Champlain Islands Marathon?

The forecast calls for a high of 57°F and a low of 42°F with a 21% chance of rain.

Historical Weather

Based on 13 years of data
Avg Temp
59°F
L:49° H:59°
RunScore
8
Conditions
Rain Freq
15%
2 of 13 yrs
Wind10mph
Dew41°F

Temperature History

Range of temperatures during race hours for each year.

Detailed History

YearConditionsLow / HighRainScoreResults
2025
clear-day
49°/70°-
7
2024
partly-cloudy-day
45°/64°-
8
2023
cloudy
46°/47°Light
8
2022
clear-day
45°/58°-
9
2021
cloudy
51°/59°-
9
2019
clear-day
50°/59°-
9
2018
partly-cloudy-day
44°/56°-
9
2017
clear-day
62°/71°-
6
2016
partly-cloudy-day
52°/57°-
8
2015
partly-cloudy-day
50°/62°-
8
2014
clear-day
46°/54°-
9
2012
rain
45°/49°Light
8
2011
cloudy
52°/57°-
9