Napa Valley Trail Half Marathon
Race Day Weather
Comfortable temps, warming through the race, chance of rain
Mild 53°F temps at gun time mean comfortable early miles without overheating risk. Temperatures rising to 64°F through the course will gradually increase perceived effort in the second half. Light winds shouldn't be a major factor for pacing. There's a chance of rain, so have a backup gear plan ready.
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Race Info
The Half Marathon is two laps of the 10K loop on the single-track trails of Bothe-Napa Valley State Park, between Calistoga and St. Helena in the Napa Valley. The course climbs through hills and crosses streams over rocky, narrow trail, with some steep drop-offs along the edge. It runs on the Saturday of race weekend alongside the marathon, 10K and 5K.
Race weekend
FAQ
When is the 2027 Napa Valley Trail Half Marathon?
What is the time limit for the Napa Valley Trail Half Marathon?
What will the weather be like for the 2027 Napa Valley Trail Half Marathon?
Historical Weather
Temperature History
Range of temperatures during race hours for each year.
Detailed History
| Year | Conditions | Low / High | Rain | Dew Point | Score |
|---|---|---|---|---|---|
2026 |  | 61°/72° | - | 54° | |
2025 | | 53°/58° | - | 50° | |
2024 |  | 50°/55° | Light | 49° | |
2023 | | 47°/55° | - | 45° |