You can swim, you can even surf, but it will be bracing, to say the least. The water temps at the Oregon Coast average in the 40s-50s year-round, so it can be a shock to the system if you’re used to more temperate waters. Fortunately, gear for cold weather swimming continues to improve, so if you really want to be able to say you swam off the Oregon Coast you can .. even in winter if you’re really determined. Oregon definitely isn’t the bikini-coast like Southern California or Hawaii. Even in summer, you’re likely to want a 1-piece suit instead, but if you’re brave and it’s a warm enough day you just might be fine in your teeny-weeny polka dot bikini after all.