Summer can be crazy busy in Napa. Traffic backs up for miles on CA Highway 29, tasting rooms burst at the seams, and everyone feels a bit frazzled. During this busy season, making winery reservations can help calm the frenzy, but plan ahead, up to a month for the most popular places.
Summer is also a good time to seek out a smaller, family-owned place off the beaten track. The valley can also be hot in mid-summer, making it a good time to explore wineries on Spring Mountain above the town of St. Helena or Howell Mountain near Angwin.
In summer, the grapevines will be growing fast. You'll see lots of activity in the vineyards: pruning and shaping them to control how much sunlight falls on the grapes. In a year when too many grape clusters form, vineyard managers also "drop fruit," leaving only a few to concentrate flavor.
If you're visiting Napa in summer because the kids are out of school, you'll find that there are many family-oriented activities as well
What It's Like in the Summer
Summer in Napa Valley runs from Memorial Day to Labor Day. Chances of rain this time of year are small. Daily highs are in the upper 70s to 80s and lows in the mid-50s.
Contrary to what you find in other places, the north end of Napa Valley is its hottest part in summer, thanks to the cooling effects of the San Francisco Bay at the south end. On a hot day, temperatures can vary by as much as 20-degrees between Carneros (coolest and furthest south) and Calistoga (hottest and furthest north).
Averages are just numbers, and what's going to happen during your trip may be different. Check the short-range forecast a few times during the week or two before you go to get a better picture of what will happen.
Pros and Cons
Summer days in Napa will be mostly clear and sunny. The vineyards are in full, green growth and the days are long, leaving time for dining alfresco after a day of wine-tasting. Many wineries host summer festivals, and it's a wonderful time of year for a winery picnic.
The biggest downside of visiting Napa in the summer is overcrowding. If summer is the only time you can go, don't let that stop you. If your schedule is flexible, consider another time of year instead.
It's easy to forget that Napa is primarily an agricultural area. The most traditional of agricultural events, the Napa County Fair, happens in July.
Summer is also concert time in Wine Country. The season kicks off Memorial Day (last Monday of May) with BottleRock Napa Valley, a 3-day festival featuring big-name music artists, food, wine, and brew. Festival Napa Valley is a star-studded music festival that lasts more than a week. Just before the weather starts to cool off, you can enjoy Music in the Vineyards, a chamber music festival with outdoor dining and music.
Instead of going to Napa in the summer when it's busy, hot and overcrowded, you might also want to visit Napa in Fall for the grape harvest, and the fall color in the vineyards.
If you go to Napa in Winter, you'll find it quiet, and you can get lots of personalized attention in the tasting rooms.
Napa in Spring is newly green, and the spring-blooming mustard can be spectacular.