Napa Valley Weather

Before you book your trip to California Wine Country, you may be wondering: when is the best weather in Napa Valley? Thanks to a mild, Mediterranean climate, Napa Valley is not only an idyllic place to grow grapes, it’s also a welcoming destination for visitors any time of year. Though temperate year-round, summers tend to be warm and dry with plenty of sun, while winters can bring rain and cooler, cloudy days. Regardless of the season, temperatures can vary dramatically between day and night, sometimes as much as 30 degrees, so layers are advised.

5 Day Forecast

From sunrise to sunset, the weather forecast is looking good in Wine Country! Thanks to its mild, Mediterranean-like climate, Napa Valley is an idyllic place to visit year-round.

When is the Best Time of year to Come to Napa Valley and Average Monthly Temperatures

Weather Season by Season


March – May

Spring is a lovely time to explore Napa Valley, when you’ll find blossoming flowers, vineyards showcasing the first signs of bud break, and fewer crowds. Though you may see patchy fog in the morning, rain becomes less frequent as the days start to warm, inviting mild temperatures that encourage more time outdoors.

Average High/Low: 68°F / 47°F
Average Rainfall: 1.8″


End of May – August

Napa Valley is a top destination during the summer months for visitors looking to make the most of the region’s long, hot days and pleasant evenings. Though it can get crowded, you can’t deny the appeal of lazy, sunshine-filled afternoons in Wine Country, when there’s not a cloud or raindrop in sight.

Average High/Low: 82°F / 55°F
Average Rainfall: 0.08″


Late August – October

California beckons with lovely weather conditions all year long, but it’s hard to beat the magic of the harvest season in Wine Country. Thanks to average temperatures that are neither too hot nor too cold, it’s an ideal time to visit. Plus, the vineyards reveal brilliant shades of red and gold that make for a beautiful sight to see.

Average High/Low: 77°F / 50°F
Average Rainfall: 0.08″


Late September – Thanksgiving

Though fall in Napa is synonymous with harvest, most of the excitement surrounding crush begins to mellow out by mid-October as evening temperatures start to drop. While still pleasant during the day with high temperatures staying in the upper 60s, layers become more of a necessity in the early morning and at night when it can dip below 45 degrees. Sunny days are still the norm, but November brings more clouds and the occasional rain shower.

Average High/Low: 69°F / 41°F
Average Rainfall: 1.9”


December – January

December is a wondrous time in Napa Valley, when festive events and gatherings add to the joy of the season. Average temperatures hover around 60 degrees during the day, dropping down into the 40s and sometimes 30s at night. Though you won’t find snow, precipitation is somewhat frequent, so don’t forget an umbrella and a rain jacket.

Average High/Low: 60°F / 42°F
Average Rainfall: 5.1″

Low Season

January – March

Winter may be the rainy season in Napa County, but with fewer crowds and more affordable lodging prices, it’s a great time to cozy up with a glass of red wine beside a fire. Despite the rain, you’ll still find clear, sunny days with a high temperature in the 50s, making Napa feel downright balmy compared to most of the country this time of year.

Average High/Low: 57°F / 38°F
Average Rainfall: 5.3″


Plan Your Trip


Airports Near Napa Valley: A Traveler’s Guide


Napa Valley Harvest Season: A Traveler’s Guide


New in Napa Valley in 2020: Where To Eat, Stay, Sip & Shop


San Francisco to Napa for the Day Trippers & Overnighters


Your Questions About Napa Valley Weather Answered

  1. When is the best weather in Napa?

    With its mild, Mediterranean-like climate, Napa Valley is an idyllic place to visit year-round. However, Napa Valley’s warmest weather is found between May and September, when the days are long and filled with plenty of sunshine.

  2. How cold does it get in Napa Valley?

    Napa Valley enjoys mild weather year-round, but winter brings the coldest temperatures. While daytime temperatures rarely drop below 55 degrees between January and March, average lows range between 38 – 40 degrees F at night.

  3. Does Napa have snow?

    While the higher elevations in Napa Valley, such as Spring Mountain, receive the occasional flurry or dusting of snow, the valley floor (where most of the vineyards are located) does not get snow.

  4. Does it rain in Napa?

    Napa Valley gets an average of 27 inches of rain per year, with most rainfall happening during the winter months between December and March.

  5. Why is the weather good for the wine?

    Napa Valley’s Mediterranean climate creates ideal conditions for growing grapes, where warm, dry summers are moderated by cool marine influences, and large diurnal temperature shifts from day to night allow the grapes to ripen while retaining balanced acidity.

  6. Is Napa Valley warmer than San Francisco?

    Napa Valley is typically much warmer than neighboring San Francisco, especially in the summer months. During summer, fog and cooler temperatures are common in San Francisco, while warm, sunny days are the norm in Napa Valley.

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