Heat is not the problem, Humidity is.
So I started riding last month while I was down in Arizona visiting family and friends. Started off horrible only able to ride two miles or so but got up to 10 or so before I left to come back home to Texas, thinking that because the heat is about the same I could likely ride about what I could before I started off on monday as if it wasn't a big deal, about four miles in I'm already dead. The humidity here is horrible, and my usual trick of using a wet bandana does nothing. Any tips on dealing with the heat while it is 50%+ humidity at all times?