Kento, Everybody from the East Coast to Southern California and from as far as NZ have offered an opinion on a wetsuit for Sonoma County and I am experiencing thread FOMO. So here is my 2c Au and highly controversial approach to wetties.
I googled Sonoma County and it is north of SF. I have lived in the Bay Area and used to surf Santa Cruz and sometimes Ocean Beach. I used similar winter attire as here in Vic. Winter climate is comparable to SF, maybe we get a bit more horrible wet weather here. Surf comparable too - the open beaches are too big and blown out half the time. So what the others say - no a 3/2 won't do it.
Wetsuits are almost like skate shoes - I don't believe in paying full price, the only reasons I can imagine for doing that is if one wanted the latest fashion or have been sucked into craving the latest tech bells and whistles that the advertising offers. A bit of forward planning and taking advantage of the adverts that pop up on our increasingly intrusive social media will always get me something on sale. Bricks and mortar surf shops at end of season can provide some bargains too.
I don't understand why anyone feels the need for a custom wetsuits - I see all sorts of sizes and shapes of human at the beach and none of them are in custom wetties. Neoprene is a very forgiving material. If it is too tight then go up a size - certain bits might be baggy, but all the name brand wetties have decent zip sealing now, so getting blown up like a balloon full of water hasn't happened to me since the 80s or 90s. All but one of my wetties are technically too big for me. The patagonia is an outlier though - even if I could get one my size I couldn't imagine going smaller than my current oversize one. It feels tight enough and getting into it would be a problem.
I might sound like I don't care about wetties, but this is not the case. I believe one of the biggest hindrances to surfing performance is being cold. Muscles are not going to operate properly. So for winter I am looking for something more than a 4/3 steamer. Always attached hoods - hoods and helmets do not affect balance once used to them. I guess they might distract the senses of someone not used to them, but cause me no problems. When it comes to warmth rubber thickness is number one. The importance of fluffy liners and smoothskin panels is completely overrated. My 5.5 Excel Comp which has no smoothskin at all is very warm and going to be warmer than some exotic fluffy lined smooth skin chest panel 4mm.
My consumption of surfboards compared to many on this forum is very modest, but I like to keep a good range in my wetty wardrobe. Maybe fixation is too strong a word, but I do have a lot of them. Spring now, but this winters wardrobe consisted of 5.5 mm hooded Xcel Comp, 5 mm hooded Xcel Drylock, 4.5 mm hooded Pattagonia, 4/3 mm hooded Vissla. Also 2 non hooded wetties for early winter and spring - 5/3 Hurley and 4/3 Narval.
Having this many wetties means it is much easier to get one or another dry for the next session even when I am doing 2 sessions in a day they get at least close to one day of drying time. It seems I am the only one who has been happy with the Pattagonia (30% off made it affordable). The rubber is stiff, but robust and retained its insulation qualities over several season. It started leaking at the end of this winter so I am no longer happy with it. The importance of stretchy rubber for paddling is completely overrated - paddling and popping to the feet is all about fitness.
I don't worry about drying them in some morning or winter sun. I do rinse them well and make sure the water flushes the inside. Hang them for a bit inside out, then turn them the other way and hang some more. Having so many wetties means that they are not spending all their time sopping wet, so they last me over 3 or more seasons. I have a tip for no smell booties - put a little bit of liquid laundry detergent in them, fill them with water then shake and stand them while rinsing the steamer. Then rinse out in the wetty bucket. On the subject of booties I have 2 pairs. 5mm get used in the morning and 3mm for the arvo session. 5mm booties are noticably warmer than 3 and good for chilly mornings. I managed to wear a hole in the sole of my left Billabong 5mm boot in one season - I think it is because it is my skimboard pushing foot.
PS I haven't covered my summer wardrobe as it is not relevant to N Cal water temps - unless one is surfing in the middle of a hot summer day (I don't do that) there would be no need for 3/2, but 3/2 is needed for summer here.