Being an Arizona scuba diver means dealing with some of the most extreme temperature swings in the sport. One weekend you are sweating on a boat in San Carlos, and the next you are dropping into a 55-degree thermocline at Lake Pleasant. So, what exactly should you be hanging in your gear closet? You can’t dive the world comfortably in just one suit. Here is our instructor-approved guide to wetsuit thickness, helping you figure out exactly what you need to own for every condition.