Clarence DeMar Marathon

Keene, NH, USA · September 26, 2027·

56°·67° high·Light·Dry

Weather

Clarence DeMar Marathon race day weather

56°at start

72° high

Breezy

Dry

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Cool start, warming trend

Runners will face a temperature increase from 56°F at the start to 67°F by the finish, with average humidity at 70%. Wind will be light from the WSW, making it a non-factor. As temperatures rise, runners should adjust their pace conservatively, especially in the later miles.

Race day forecast available in 302 days

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Distance: 26.2mi

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About the Clarence DeMar Marathon

The Clarence DeMar Marathon offers a scenic 26.2-mile journey through New Hampshire's picturesque countryside, featuring gentle rolling hills and a net elevation drop that makes it a prime Boston Marathon qualifier. Runners are treated to stunning views of early autumn foliage, with the course culminating at the historic Appian Way of Keene State College, near where marathon legend Clarence DeMar once coached collegiate runners. The event is renowned for its exceptional organization and the enthusiastic support of over 300 volunteers, creating a welcoming atmosphere for participants of all levels.

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Race weekend

Sunday, September 26

7:00 AMMarathon (26.2 mi)

8:00 AMHalf Marathon (13.1 mi)

Course Map

Clarence DeMar Marathon FAQ

When is the 2027 Clarence DeMar Marathon?

The 2027 Clarence DeMar Marathon will be held on Sunday September 26, 2027.

Is the Clarence DeMar Marathon a Boston Marathon Qualifier?

Yes, the Clarence DeMar Marathon is an official Boston Marathon qualifier.

What is the time limit for the Clarence DeMar Marathon?

The time limit for the Clarence DeMar Marathon is 7 hours.

What will the weather be like for the 2027 Clarence DeMar Marathon?

The forecast calls for a high of 70°F and a low of 53°F with a 10% chance of rain.

What is the weather usually like for the Clarence DeMar Marathon?

Over the 18 years racecast.io has race-day weather for (2008 to 2026), it averaged 51°F at the start and 62°F by a typical finish. Rain fell during race hours in 3 of those years (2009, 2018 and 2026).

What was the hottest Clarence DeMar Marathon?

Of the 18 years on record, 2017 was the warmest, reaching 80°F during race hours. The coldest start was 2015, at 34°F.

What was the windiest Clarence DeMar Marathon?

Of the 18 years on record, 2026 was the windiest, with wind averaging 13 mph during race hours. The calmest was 2013, at 0 mph.

Clarence DeMar Marathon weather history

Based on 18 years of data

Avg Temp

55°F

L:51° H:62°

RunScore

Conditions

Rain Freq

17%

3 of 18 yrs

Wind3mph

Dew51°F

Temperature History

Range of temperatures during race hours for each year.

Detailed History

Year	Low / High	Rain	Dew Point
2026 Clarence DeMar Marathon Cloudy skies throughout the day. 2026	57°/57°	Light	55°
2025 Clarence DeMar Marathon Clear conditions throughout the day. 2025	57°/70°	-	60°
2024 Clarence DeMar Marathon Partly cloudy throughout the day. 2024	57°/62°	-	54°
2023 Clarence DeMar Marathon Cloudy skies throughout the day with rain. 2023	52°/58°	-	50°
2022 Clarence DeMar Marathon Partly cloudy throughout the day with late afternoon rain. 2022	40°/55°	-	44°
2021 Clarence DeMar Marathon Partly cloudy throughout the day. 2021	53°/66°	-	53°
2019 Clarence DeMar Marathon Clearing in the afternoon. 2019	61°/64°	-	50°
2018 Clarence DeMar Marathon Partly cloudy throughout the day with morning rain. 2018	42°/53°	Light	45°
2017 Clarence DeMar Marathon Clear conditions throughout the day. 2017	55°/80°	-	60°
2016 Clarence DeMar Marathon Clearing in the afternoon. 2016	36°/54°	-	38°
2015 Clarence DeMar Marathon Clearing in the afternoon. 2015	34°/54°	-	35°
2014 Clarence DeMar Marathon Clearing in the afternoon. 2014	54°/66°	-	49°
2013 Clarence DeMar Marathon Partly cloudy throughout the day. 2013	44°/59°	-	43°
2012 Clarence DeMar Marathon Partly cloudy throughout the day with late afternoon rain. 2012	54°/55°	-	52°
2011 Clarence DeMar Marathon Partly cloudy throughout the day. 2011	64°/69°	-	64°
2010 Clarence DeMar Marathon Partly cloudy throughout the day. 2010	49°/65°	-	47°
2009 Clarence DeMar Marathon Cloudy skies throughout the day with a chance of rain throughout the day. 2009	50°/57°	Light	51°
2008 Clarence DeMar Marathon Cloudy skies throughout the day with rain. 2008	63°/68°	-	62°