Heatwave population

Apart from one late afternoon early evening stay about a month ago, I havent been in a while but I am itching to get stuck in (so to speak). But have been wondering what the population is like during the hot weather?
You’d think getting to go to a place where you can get naked would be a perfect cooling off. But it is a Sauna, and getting busy in those private rooms probably heat things up. So I wanted to make sure I came at a nicely populated time.