I am thinking of signing up for my first (sprint) triathlon this year. It will be at the end of June near Denver, CO. The website says the water is usually in the low to mid 70s (F) that time of year.
Has anyone else done a summer triathlon in Colo? Or in similar water temperatures? Do you think I need a wetsuit? Or maybe just a wetsuit top? If I got a wetsuit, would a sleeveless be OK?

To me that sounds cold - I am a wimp in the cold any time of year!
thanks!