For decades, San Francisco was one of the favorite cities for surfers and windsurfers. In recent years, it has also become an established kitesurfing destination with dozens of rentals and schools. The weather is quite predictable in San Francisco, where it's possible to enjoy water sports year-round thanks to the Mediterranean climate. However, the best time is from March through October when the wind is the strongest. The western wind is prevailing in the summer, although its direction often changes to the East. San Francisco Bay water temperature stays about 50-60°F (11-17°C). The wind usually picks up at the end of the afternoons.
The most popular kitesurfing spot in the city is Ocean Beach, specifically its northern part. The beach is large enough to unfold the kites, and the water is flat and comfortable for kiteboarders of various levels. Crissy Field is another famous kitesurfing location, but winds here are stronger, so it might be a more challenging spot for newbies. If you move away from the city, Stinson Beach (off Highway 1) near the Golden Gate National Recreation Area attracts many kiteboarders during the summer. South of San Francisco, San Mateo, offers a beautiful area favored by kiters. In particular, 3rd Avenue in San Mateo offers good swell and winds especially for kitesurfing lessons in the channel.
As for windsurfing, Coyote Point Park and Crown Beach in San Mateo are the best locations in the Bay Area. Many schools offer lessons and windsurfing gear like the board, sail, and wetsuit. Rio Vista attracts many windsurfers since it boasts strong and steady winds coming from the river. In about 40 min. drive, Davenport Beach is a great spot that attracts many experienced windsurfers. The wind here is too strong for kitesurfers and beginner windsurfers, so you'll mostly see a pro windsurf crowd.