The best time to go depends on what you're looking for. The grape crush in September and October brings Foodies flock to the landmark tables serving dynamic wine country cuisine. Here, dessert time at the boisterous new Bistro Jeanty. November see warm weather and fewer people, which means a table is easier to come by and locals a lot friendlier. Although wineries and restaurants are open year-round, expect some rain December through March.
Most restaurants require two weeks' to one month's notice for a weekend night.
Consider lunch in lieu of dinner at a high-end restaurant. You can sample the same food for less money and can often get a table just a few days ahead. Leave your name on a waiting list. Most places confirm reservations the night before and fill cancellations from their list. Call around 5 PM to check on day-of dropouts.