The Napa Valley—with its Mediterranean climate, small towns, architecturally distinct and world-renowned wineries, and miles of vineyards flanked by mountain ranges—can be visited year-round. But most of the estimated 4.7 million oenophiles who visit annually flock to the region on summer weekends and during the fall grape harvest. During this time, two-lane Highway 29, the valley’s main artery, seems more like traffic-choked U.S. Route 101 than the quiet country road that it can be the rest of the year. Summers stay pretty toasty, with temps that can reach into the 100s in July and August. Fall can bring spectacular Indian summers that hold in the 80s well into October. You’ll find less traffic and more attentive service at winery tasting rooms during weekdays or anytime during off-season, particularly winter months. From December to February, the days are shorter and the temps are chilly (but not cold), lingering around 50 degrees.
Several festivals draw thousands of visitors to Napa each year. There’s the Napa Valley Wine Auction in June, the arts-and-culture-focused Festival del Sole in July, the Mondavi Winery summer concert series, and Yountville’s Festival of Lights in December.