Our plan is to hit Sonoma County on Labor Day. Would you focus on the wineries that do not require reservations, or would it make more sense to go where reservations are required to guarantee a spot?
Reserve. It's a 3 day weekend. A LOT of locals will be up there. And they know where they want to go and will have made plans.
Labor and Memorial Day weekends are the few where SF neighborhood street parking and cool local restaurant reservations are available. You know where all those folks are?Edited: 14 May 2018, 09:16
I Was worried about Monday, but also hoping by then it might start tapering off. I’m starting to narrow down my winery choices, so will consider making reservations. We think we would like to do the wine train on Tuesday and that would cover Napa for us. Maybe we will consider Sonoma on Wednesday. We have all that day, just heading to the airport hotel that night for our flight out on Thursday. Monday could then become our “free” day to explore some of the towns.
The Monday of a three day weekend is almost always less busy than the weekend itself although still busier than a normal weekday. If there are wineries you want to visit that require reservations, it's always best to make them whether it's a holiday or not.