Diablo Trail Marathon

Clayton, CA, USA · May 23, 2027

58°·73° high·Light·Dry

Weather

Race Day Weather

58°at start

73° high

Breezy

Dry

Warm day, strategic pacing needed

Runners will face temperatures starting at 59°F and rising to 77°F, with an average humidity of 59%. A headwind will challenge runners from miles 1 to 6, and again at 8 and 14, necessitating pace adjustments. The terrain's significant climbs from miles 1 to 7 and 16 to 21 will require careful energy management, while tailwinds from miles 7 and 20 can aid during descents.

Race day forecast available in 232 days

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Distance: 26.2mi

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Race Info

Mount Diablo provides spectacular views of the San Francisco Bay Area and surrounding valleys. The 4 mile course is relatively flat and fast within Mitchell Canyon. The longer events are mountainous and very scenic. Source

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FAQ

When is the 2027 Diablo Trail Marathon?

The 2027 Diablo Trail Marathon will be held on Sunday May 23, 2027.

What will the weather be like for the 2027 Diablo Trail Marathon?

The forecast calls for a high of 75°F and a low of 52°F with a 1% chance of rain.

Historical Weather

Based on 14 years of data

Avg Temp

72°F

L:61° H:82°

RunScore

Conditions

Rain Freq

14%

2 of 14 yrs

Wind7mph

Dew51°F

Temperature History

Range of temperatures during race hours for each year.

Detailed History

Year	Low / High	Rain	Dew Point
2026 Diablo Trail Marathon Clear conditions throughout the day. 2026	60°/78°	-	50°
2025 Diablo Trail Marathon Clear conditions throughout the day. 2025	64°/81°	-	55°
2024 Diablo Trail Marathon Clear conditions throughout the day. 2024	60°/92°	-	51°
2023 Diablo Trail Marathon Clear conditions throughout the day. 2023	58°/83°	-	53°
2022 Diablo Trail Marathon Partly cloudy throughout the day with rain. 2022	63°/71°	Light	55°
2021 Diablo Trail Marathon Clearing in the afternoon. 2021	60°/79°	-	54°
2019 Diablo Trail Marathon Clear conditions throughout the day. 2019	67°/92°	-	57°
2018 Diablo Trail Marathon Clear conditions throughout the day. 2018	58°/78°	-	52°
2017 Diablo Trail Marathon Clear conditions throughout the day. 2017	68°/101°	-	55°
2016 Diablo Trail Marathon Clearing in the afternoon. 2016	61°/80°	-	52°
2015 Diablo Trail Marathon Clear conditions throughout the day with afternoon rain. 2015	65°/82°	Light	53°
2014 Diablo Trail Marathon Clear conditions throughout the day. 2014	58°/80°	-	52°
2013 Diablo Trail Marathon Clear conditions throughout the day. 2013	56°/80°	-	25°
2012 Diablo Trail Marathon Clear conditions throughout the day. 2012	54°/80°	-	51°