In 7 days · Sat, Oct 17, 2026
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Saturday, October 17th, 2026
Castle Rock Rd, Walnut Creek CA
Half · 5K · 10K
55–76°F · low rain risk
See last 10 years
On this date: rain 1 of the last 10 years
2025
49–72°F
dry
2024
54–74°F
dry
2023
60–83°F
dry
2022
52–74°F
dry
2021
49–71°F
rain
2020
65–92°F
dry
2019
55–71°F
dry
2018
50–79°F
dry
2017
59–85°F
dry
2016
53–67°F
dry
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Race-day forecast · Saturday, Oct 17
Sunny · 61–92°F
Saturday, Oct 17starts near 61°F · 0% chance of rain · wind up to 5 mph
About this race
Event Overview
Join us for the Diablo Summit Stomp 2026 on 2026-10-17 at Castle Rock Rd, Walnut Creek, CA. For more information, visit the race page.
Course Details
- Terrain: All courses are on trails.
- Difficulty: While there are some hills, this event is very friendly to first-time trail runners and experienced runners alike.
- Participants: Walkers/hikers are welcome in all distances.
Awards
- Age Group Awards: Awards will be given to the top 3 finishers in 5 year categories.
- Younger Category: Smaller categories for the younger ages.
Course map
Train with a club
Run clubs near Walnut Creek to train with before race day.
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