65 degrees

Hi everyone I am semi new to open water swimming and can only count two open swims so far. both were one milers and the water was pretty calm, and more importantly the water was warm, in the high 70s. I am also a newer masters swimmer, and typically swim 3-4 x a week at 3,300 yards. I signed up for a one mile swim in the Hudson in a week and I see that the water temperature is around 65 degrees. I am borrowing a friend's wet suit, a half sleeve and it comes down to the knees, but I have never swum in water that cold before. Does any have any advice on whether i should attempt it or scrap it? Amy