IMHO balls are best kept with humidity levels of 50%-60% and slightly higher when in a shed, with a temperature gradient of 80 (ambient/cool) - 90 (warm side). Though they can be kept with a warmer hot spot, I find they don't make good use of it, I find they fare best at these temps. 90 degrees is far too warm to be keeping a snake at unless you are battling an RI. Your snake needs a cool retreat in his home. Hope this helped