The hot spot is going to come from either a UTH or Heat Lamp. UTH is preferred and UTH won't effect your humidity. I had my heat lamp on the same side as my UTH. This gave me a perfect hot side and has the heat dissipated, gave me a perfect cool side of 80 degrees. I found this on another site, I used this when setting up my cage. The only difference is my water dish was in the middle.
http://i1250.photobucket.com/albums/...psf55661d3.png