The 2025 event has concluded.

Humboldt Bay Marathon

Eureka, CA, USA • August 10, 2025
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Race Day Weather

partly-cloudy-day
52°
65° high
Breezy
Dry

Comfortable temps, warming through the race

Mild 52°F temps at gun time mean comfortable early miles without overheating risk. Temperatures rising to 65°F through the course will gradually increase perceived effort in the second half. Light winds shouldn't be a major factor for pacing. High humidity (88%) will make it harder to cool down through sweat — increase fluid intake accordingly.

partly-cloudy-night9
cloudy8
partly-cloudy-day9
cloudy9
partly-cloudy-day8
partly-cloudy-day9
partly-cloudy-day9
clear-day9
clear-day9
clear-day9
clear-day9
Pre-raceRace windowPost-race

Pace Calculator

Distance: 26.2mi
0:00:00
HH:MM:SS
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Area Map

Course Map

Course Map Unavailable

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FAQ

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When is the 2025 Humboldt Bay Marathon?

The 2025 Humboldt Bay Marathon will be held on Sunday August 10, 2025.

Is the Humboldt Bay Marathon a Boston Marathon Qualifier?

Yes, the Humboldt Bay Marathon is an official Boston Marathon qualifier.

Historical Weather

Based on 8 years of data
Avg Temp
64°F
L:55° H:64°
RunScore
8
Conditions
Rain Freq
13%
1 of 8 yrs
Wind11mph
Dew57°F

Temperature History

Range of temperatures during race hours for each year.

Detailed History

YearConditionsLow / HighRainScore

2024 Humboldt Bay Marathon

Cloudy skies throughout the day.

2024
cloudy
55°/61°-
9

2023 Humboldt Bay Marathon

Partly cloudy throughout the day.

2023
cloudy
55°/65°-
8

2022 Humboldt Bay Marathon

Partly cloudy throughout the day.

2022
cloudy
58°/63°-
9

2019 Humboldt Bay Marathon

Clear conditions throughout the day.

2019
partly-cloudy-day
53°/68°-
8

2018 Humboldt Bay Marathon

Partly cloudy throughout the day.

2018
cloudy
57°/63°-
9

2017 Humboldt Bay Marathon

Partly cloudy throughout the day.

2017
clear-day
54°/68°-
8

2016 Humboldt Bay Marathon

Cloudy skies throughout the day with morning rain.

2016
fog
51°/60°Light
8

2015 Humboldt Bay Marathon

Partly cloudy throughout the day.

2015
partly-cloudy-day
56°/66°-
8
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