Base layer is very important.
RedHead, Underarmour, etc..
make good base layer long underwear. It has to be able to wick away moister. Once you have the proper base, like as already been said, layer up.
Wool is good but the top layer must be able to comfortably block the wind.
Just be careful, what happens when you layer up? you loose mobility. I know if I went in with winter clothes on and sea boots that I would be in very big trouble, especially with the water temps what they are. Remember, stay on board.
FYI, I am in the midwest, I have a crazy buddy who has left his boat on the water, a 21 footer on an inland lake. We plan on going out this weekend. Temps should be in the mid 30's.
Courtney is My Hero
If a man is to be obsessed by something, I suppose a boat is as good as anything, perhaps a bit better than most - E.B. White