Kinda, unless you're from up north.
I've gone to IOA a few times in February. Low temps are 55, but then it warms up to 75 in the afternoon. The thing is, the water temperature is the same no matter what, it's like a cold shower. Once you get in the water you kinda get used to it. I'd call them and ask what they think. I mean, some people from up north are used to it and go skiing in a t-shirt.