If you are visiting all the Wineries, you probably will find this, if not here it is:

Stony Ridge Winery. They also have a great restuarant on premises. The desserts are to die for and they also have very good dessert wines.

BTW, don't even try to get on the 680/580 freeways during the following hours: 6a - 9a and 2p - 6p, because the traffic is horrible.