for paddling. Most will recommend 3 mm for occasional immersion and that will work fine for most people down to about 55F. I've worn a 3mm suit for ocean activities in SF and Monterey bay (and the coast south of Monterey) and it is fine, for me, anyway down to 55F or so.
Below that, a dry suit is preferable to a wetsuit since it allows more freedom of movement. I have a 7mm suit for SCUBA and it is not something I could sit or paddle in for any length of time. It resists motion and limits comfort if you try to bend it more than it really wants to. Bending these suits will, over time, degrade the suit. It will tend to compress, fold, and eventually crack if you try to force it into shapes it doesn't really want to take.
Free Standing Boat Racks
The Kayak Wing
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