What to expect depends on what time you're going on Monday. Slack before flood is around 10:30 AM, and slack before ebb is around 4:25 PM. Since there's a fairly large exchange (a bit over 10 feet) in the interrim, you'll want to plan your dive around one or the other slack period. So plan to splash either at 10 AM or 4 PM.
If you choose the morning slack (SBF), you'll be able to walk out to near the end of the jetty before you begin your surface swim. The down side is that the vis probably won't be as good, and you'll max out at around 30 fsw. The up side is that as soon as you're in 5 or 6 feet of water you'll be able to drop down and pick up a rope trail.
If you chose the afternoon slack (SBE), you get a longer surface swim, better vis, and more depth.
Either way, my favorite dive plan (and the one I took this morning) is to swim out to the end of the jetty, at about 100 feet off the end, descend and take a 345 degree heading till you pick up a rope line heading roughly west. That's Jetty Way. It's a bit difficult to actually see the rope this time of year, so just look for a kelp bed growing in a straight line that's cutting a 5-foot wide swath through the eel grass, and you've found it. Follow this out till you come to an intersection marked by a pair of large brass boat propellors (one on either side). Take a right (heading north) and follow this trail. It's easier, because the rope is propped up on milk containers. About 2 minutes along here you'll come to a room-sized concrete block ... that's the first of the Cathedrals. There are four or five of them, and I'd recommend spending some time poking around these for a while ... a really nice place to find critters large and small. On the north side of Cathedrals you'll find another rope trail heading west ... follow it west till you get to the first intersection ... the rope trail heading north from there is spun through large plastic spools. Head north on this for about a minute or two and you'll see the Triumph ... a roughly 75-foot wooden vessel, looming close by the west side of the rope trail. Do a circuit around it ... I usually like to start by going underneath the rudder, shining my light up at the anemone-covered bottom for all the little critters that like to make a home there. As you approach the bow, keep a wary eye out for an overly aggressive cabezon who hasn't figured out that it's not yet mating season ... he'll charge you if you get too close.
Once you complete the circuit, you'll see a smaller boat (30-foot Chris Craft) laying roughly 10 feet from the starboard bow of the Triumph. From that boat you can pick up a diagonal rope trail that brings you past another small boat and back to Cathedrals. You can at that point reverse your course and go back in on Jetty Way.
The park is shallow, and at times the bottom has virtually no slope at all. If you lose a rope trail, keep in mind that west is out and east is in and you'll find your way around with no problems.
The dive plan I outlined above will take you anywhere from 40 to 60 minutes, depending on how fast you swim, how much you stop to look at stuff, and whether you do it on a high or low tide.
Water temp today was 56 degrees F ... about as warm as it gets. A 6 or 7 mil wetsuit will be fine for a single dive ... and with the exchanges on the 22nd, I would not recommend a second one unless you're a strong swimmer. Currents run counter to what you'd expect, due to the eddy caused by shore formation and the jetty ... the current goes south on an ebb and north on a flood.
PS - if someone tries to talk you into doing the dry dock, and you're not familiar with the park, take a pass ... that's how people end up in the ferry lane.
Let me know if you have any more questions ... and have fun.
... Bob (Grateful Diver)