San Lorenzo River Trail Run

Santa Cruz, CA, USA · July 10, 2027
partly-cloudy-day60°·67° high·Light·Dry
6
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Race Day Weather

partly-cloudy-day
60°at start
69° high
Light
Dry

Comfortable temps

Starting at 60°F, heat will be a factor from the gun — go out conservative and stay on top of hydration. Temperatures rising to 69°F through the course will gradually increase perceived effort in the second half. Light winds shouldn't be a major factor for pacing. Moderate humidity at 74% is worth noting for effort level, especially in later miles.

Race day forecast available in 271 days
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Race Info

The San Lorenzo River Trail Run is an annual trail race in Santa Cruz, California, organized by Coastal Trail Runs. Held each July, it starts and finishes at Harvey West Park and offers 10K, Half Marathon, 30K, Marathon, and 50K distances, with the marathon run as two half-marathon loops. The course crosses the San Lorenzo River multiple times and passes through coastal redwood forest, stream canyons, and chaparral ridges toward Henry Cowell Redwoods State Park. Source

Race weekend

Saturday, July 11
7:50 AMKid's Run (0.2 mi)
8:00 AM50K (31.1 mi)
8:00 AM30K (18.6 mi)
8:00 AMHalf Marathon (13.1 mi)
8:15 AM10K (6.2 mi)
Saturday, July 10
Marathon (26.2 mi)
Area Map

Course Map

FAQ

When is the 2027 San Lorenzo River Trail Run?

The 2027 San Lorenzo River Trail Run will be held on Saturday July 10, 2027.

Is the San Lorenzo River Trail Run a Boston Marathon Qualifier?

No, the San Lorenzo River Trail Run is NOT a Boston Marathon qualifier.

What will the weather be like for the 2027 San Lorenzo River Trail Run?

The forecast calls for a high of 69°F and a low of 56°F with a 0% chance of rain.

Historical Weather

Based on 17 years of data
Avg Temp
62°F
L:56° H:68°
RunScore
6
Conditions
Rain Freq
6%
1 of 17 yrs
Wind5mph
Dew53°F

Temperature History

Range of temperatures during race hours for each year.

Detailed History

YearConditionsLow / HighRainScore
2026
partly-cloudy-day
56°/70°-
6
2025
partly-cloudy-day
54°/67°-
7
2024
cloudy
57°/67°-
6
2023
cloudy
55°/69°-
6
2022
clear-day
56°/66°-
7
2021
partly-cloudy-day
57°/70°-
6
2020
partly-cloudy-day
56°/64°-
7
2019
partly-cloudy-day
55°/73°-
6
2018
partly-cloudy-day
60°/68°-
6
2017
cloudy
58°/68°-
6
2016
partly-cloudy-day
55°/72°-
6
2015
partly-cloudy-day
57°/68°-
7
2014
cloudy
57°/69°-
6
2013
partly-cloudy-day
54°/72°-
6
2012
partly-cloudy-day
56°/64°Light
7
2011
partly-cloudy-day
55°/66°-
6
2010
clear-day
61°/72°-
6