In my experience, doing 3-6 reps is the sweet spot for this type of training. As this is done in a circuit fashion with incomplete rest, you'll be unable to perform the same loads as during traditional lifting sessions.
The water on your body changes to a gas called water vapor. Water turns into a gas through a process called evaporation. Heat makes water evaporate faster. All air has some water vapor. Tropical rain forests and deserts are both hot.
This effect will slow the evaporation down quite a a lot because the evaporation rate is proportional to the difference between the vapor pressure and the partial pressure of the substance, and diffusion can only take water away so fast.