I loved that "dry heat." - sarcasm intended. Summer in Afghanistan was regularly 115-120 (in pants and a jacket, no less). Just sitting around I drank probably close to 1 gallon of water daily. Talking to some of the more active troops, they went through 2-3 gallons of water a day.

Anyway, that's hot, and pretty dumb to go out in it. Unless you go out regularly to that heat, you're not acclimated ("I've lived here all my life" usually means ".. .with air conditioning."). Even if you have enough water, it's possible to overheat faster than you can cool.