Calistoga to Napa down the Silverado Trail, a small, scenic destination race. Early March in wine country is cool and often wet, with fog that burns off mid-race.
By Brett Heimlich, part-time runner.
Plan for about 41°F (5°C) at the 07:00 start, feeling like 37°F (3°C), with 89% humidity and 4 mph wind, warming to roughly 54°F (12°C) by the finish. It rained on 5 of the last 10 race days. Wear: Long Sleeve Tech Shirt, Running Tights, Running Cap, Waterproof Jacket.
41°F (5°C)
54°F (12°C)
5 of 10 years
33° to 52°F
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Conditions at the 07:00 start on the race's usual date each year (first Sunday of March). Years when the race was cancelled or moved still show that date's weather. Source: Open-Meteo ERA5 archive.
| Year | Start temp | Feels like | Finish | Humidity | Wind | Rain | Sky |
|---|---|---|---|---|---|---|---|
| 2025 | 45°F (7°C) | 41°F | 55°F | 96% | 5 mph | – | Clear |
| 2024 | 40°F (4°C) | 35°F | 51°F | 92% | 5 mph | 0.34 in | Mostly clear |
| 2023 | 38°F (3°C) | 33°F | 50°F | 86% | 5 mph | 0.34 in | Mostly clear |
| 2022 | 36°F (2°C) | 32°F | 58°F | 84% | 2 mph | – | Clear |
| 2021 | 38°F (3°C) | 32°F | 59°F | 81% | 4 mph | – | Clear |
| 2020 | 43°F (6°C) | 39°F | 57°F | 85% | 1 mph | – | Overcast |
| 2019 | 52°F (11°C) | 51°F | 56°F | 96% | 1 mph | 0.11 in | Overcast |
| 2018 | 33°F (1°C) | 28°F | 51°F | 92% | 3 mph | – | Clear |
| 2017 | 41°F (5°C) | 36°F | 46°F | 92% | 5 mph | 0.16 in | Mostly clear |
| 2016 | 47°F (8°C) | 44°F | 57°F | 89% | 4 mph | 0.74 in | Clear |
Coldest start: 33°F (1°C) in 2018. Warmest: 52°F (11°C) in 2019. Wettest: 0.74 in in 2016.
Built from the 10-year average start conditions by the same engine as the live tool. Treat optional items as corral-only layers you can shed.
Long Sleeve Tech Shirt
Breathable moisture-wicking fabric
Waterproof Jacket
Breathable rain protection
Running Tights
Full-length compression tights
Light Gloves
Thin running gloves
Headband
Ear coverage without overheating
Running Cap
Keep rain out of eyes
Trail or Waterproof Shoes
Better grip and water resistance
Wool Running Socks
Warm and moisture-wicking
✓ Worn by the author
Grid-fleece quarter zip for 25 to 40°F starts
$128
✓ Worn by the author
Compression tight for 40 to 55°F, works under shorts
$78
Touchscreen-compatible, windproof, and packable
$55
Warm, itch-free merino blend for cold runs
$38
✓ Worn by the author
Thin, ribbed quarter sock that keeps grit out
$36
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Over 2016 to 2025 the start averaged 41°F (5°C) (feels like 37°F (3°C)) with 89% humidity and 4 mph wind, warming to about 54°F (12°C) by the finish. It rained measurably on 5 of those 10 race days. The coldest start was 33°F (1°C) in 2018; the warmest was 52°F (11°C) in 2019.
For a typical 41°F (5°C) start: Long Sleeve Tech Shirt, Running Tights, Running Cap, Waterproof Jacket. Dress for about 15°F warmer than the start temperature, since the race itself adds that much, and plan to shed anything you only need in the corral.
The Napa Valley Marathon is usually held on first Sunday of March. The next expected date is Sunday, March 7, 2027. Confirm on the official site, since dates occasionally move.
The live forecast on this page comes from Open-Meteo and unlocks 16 days before the race. Forecasts inside 7 days are reliable for temperature within a few degrees; rain timing firms up in the last 2 to 3 days. Until then, the 10-year history above is the best planning guide.
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