Only one I can think of is Clematis tangutica - not sure whether that's hardy where you are, though its fully hardy in Britain, unlike Fremontodendron, which needs a very sheltered situation.

I think it is (after a quick internet search for it's U.S. hardiness zone)! Thank you very much. For the record, you guys are quite a bit warmer than me. I'm sooo jealous!!!!! :)

It's the Gulf stream that does it - if it ever stops, we'll be as cold as colder parts of Canada, we're on the same latitude. Fingers crossed...