The entire North Bay is a long exposed paddled but with scenery to die for especially during a stormy winter day (see below). It is situated next to a very large San Pablo Bay National Wildlife Refuge managed by US Fishing and Wildlife. The amount of birds I saw was incredible in the winter time. And compared to the south bay, this area is so much wilder. You really feel like you're alone here which I guess can be good or bad. Coming into Vallejo can be just as intimidating because the Carquinez Bridge spans more than half of a mile and the Sacramento Delta and the Napa River drains out of there. The current at the bridge can be very strong during the winter because of the runoff in addition to the tides. There are also ferries that runs from Vallejo to San Francisco during commute hours and they are FAST. You can break up this section to some smaller paddles around the San Pablo National Wildlife Refuge. Sonoma Creek would be interesting to explore; Skaggs Island must be a nice place to paddle; Napa River is of course a great place to paddle as well. The issue with this long paddle is that you need to be self-sufficient and have stamina. Even under favorable conditions, it took about 5 hours to paddle about 17.5 miles (with some detours see below). Bring plenty of food, water and layers.
On January 19th, I paddled this stretch by myself with Isabella Wilk driving shuttle. I caught a nice day between the winter storms with supposedly W/SW wind and slack to flood tides. It was a beautiful day with fantastic rainbows looking to the north that pretty much followed me the entire day. There was some small rain storms, but very minimal. Sometimes the wind would shift directions but I had it easy most of the time. The current was fairly strong near the bridge with the delta draining out. There was a lot of floating debris - large trees and branches. I caught the ferry wake a couple of times passing the bridge. The wakes were pretty small compared to the wakes near Golden Gate bridge, but the speed of the ferry was much faster.
Hazards: Long exposed paddle, make sure you bring a marine radio for emergencies calling for the coast guard. Even when you call them it could take a long time for them to get to you because they have to come from Vallejo. Carquinez Bridge and the ferries are also major hazards.
Put-in: Outdoor Adventures has their put-in site at Buck's Launching and is very friendly to small boaters. There are porte-potties at the site and water. Buck's Launching is at the mouth of Las Gallina's Creek (Gallina in Spanish means Chicken but the yellower, fattier and older kind of meat rather than the young, white meat or Pollo). Hence the muddy waters. I'm not sure about the history of Buck's but apparently it has been there for many years. It has closed now and the property is sold to the State Parks. Apparently there'll be a full state park area with small and big boat launch from this site.
Take-out: There are multiple places to take out in Vallejo. Lots of Marinas and even more public ramps in Benicia. The Benecia Outrigger Club is a great resource around there. I'm not sure whether it would be okay to take out in the summer time at Glen Cove Marina, but in the winter there was no one there so the guest dock was open to the public.