Runners will face a temperature rise from 47°F at the start to a comfortable 63°F by the finish, with humidity averaging 60%. A light tailwind will assist from miles 1-3 and 9, while crosswinds will challenge runners from miles 4-8 and 10-27. It's advisable to maintain a steady pace early and stay hydrated, particularly as temperatures increase.
Race day forecast available in 184 days
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Distance: 26.2mi
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Race Info
The Napa Valley Marathon is an annual marathon, half marathon, and 5K in Napa County, California. The USATF-certified marathon course begins in Calistoga at the northwestern tip of Napa County, and then traverses the Silverado Trail, ending in downtown Napa. The race's course is primarily rolling hills or flat as it moves through rural California Wine Country. The Napa Valley Marathon has been run in March since 1979, accepts only about 3,000 runners, and is widely considered one of the most scenic marathons in the United States. The men's and women's winners of the race win their weight in wine.Wikipedia
The 2027 Napa Valley Marathon will be held on Sunday March 7, 2027.
Is the Napa Valley Marathon a Boston Marathon Qualifier?
Yes, the Napa Valley Marathon is an official Boston Marathon qualifier.
What is the time limit for the Napa Valley Marathon?
The time limit for the Napa Valley Marathon is 6 hours.
What will the weather be like for the 2027 Napa Valley Marathon?
The forecast calls for a high of 66°F and a low of 47°F with a 8% chance of rain. Check our detailed hourly forecast above for the best marathon race plan.
Historical Weather
Based on 26 years of data
Avg Temp
59°F
L:48° H:59°
RunScore
Conditions
Rain Freq
50%
13 of 26 yrs
Wind12mph
Dew45°F
Temperature History
Range of temperatures during race hours for each year.