Napa Valley weather in September
Planning a journey to Napa Valley this September and curious over the weather conditions to await? Your essential details are found on this page, answering your query:
What is the weather like in Napa Valley in September?
Napa Valley is a region in the United States of America. September in Napa Valley generally has temperatures that range from warm to very warm, with almost no precipitation. The month of September is in the summer season.
The average highest temperatures fluctuate between warm in American Canyon at 28°C to very warm in Calistoga at 31°C. Nighttime temperatures generally drop to 11°C in Calistoga and 11°C in American Canyon. On average, September is the warmest month of the year in Napa Valley. So be prepared and pack summer clothes.
September is a very dry month with an average rainfall of around 3.8 mm in Napa. The days are mostly sunny, with an average total of around 275 hours of sunshine in Napa. The sunlight during this month doesn't just make the days brighter, it also seems to make everyone a bit more cheerful.
To learn more about the conditions in specific areas of Napa Valley in September, check out the map below. For more details on the yearly weather, visit our Napa Valley climate page.
Where to go in Napa Valley in September
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Popular destinations
What is the weather like in September for the 5 most popular destinations in Napa Valley?
Napa
In September Napa generally has high temperatures with maximum daytime temperatures around 30°C, minimum nighttime temperatures around 12°C and almost no monthly rainfall. So on average the conditions are perfect that month.
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Calistoga
In September Calistoga generally has very high temperatures with maximum daytime temperatures around 31°C, minimum nighttime temperatures around 11°C and low monthly rainfall. So on average the conditions are perfect that month.
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St. Helena
In September St. Helena generally has very high temperatures with maximum daytime temperatures around 31°C, minimum nighttime temperatures around 12°C and almost no monthly rainfall. So on average the conditions are perfect that month.
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Yountville
In September Yountville generally has very high temperatures with maximum daytime temperatures around 30°C, minimum nighttime temperatures around 11°C and almost no monthly rainfall. So on average the conditions are perfect that month.
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American Canyon
In September American Canyon generally has high temperatures with maximum daytime temperatures around 28°C, minimum nighttime temperatures around 11°C and almost no monthly rainfall. So on average the conditions are perfect that month.
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Is your destination not in the list? Have a look at other destinations in Napa Valley, in the United States of America.
Is September the best time to visit Napa Valley?
We consider September to be one of the best times to travel to Napa Valley. Typically, the climate in Napa is perfect.
On average, the best time to visit Napa Valley is in April, May, June, July, August, September and October with generally perfect weather in Napa. On the other hand, the weather in February and December tend to be unpleasant.
Interested in more climate information?
We have much more information about the climate in Napa Valley.
Interested in the weather conditions in a specific month? Select the month below.
Weather and climate has detailed information for every country in the world. Are you going to the United States of America? Get detailed historical weather averages for many cities in the United States of America.
Not sure yet where to go? We now have a tool which recommends destinations that suit your ideal climate conditions. Find out where to go with our weather planner.