Yes the weather there can really beat you up ! When I was there a few years ago helping out some friends racing JrFuel we had real high grains of water in the air, track temp was like 140°, and of course the air temp was over 100°. The racers were coming back from a run looking like ghosts.
So Please take care of yourself, drink more water than you think you can handle, wet rags, from your ice chest, around your neck, and even better gel ice packs inside your firesuit in the small of your back [ high blood flow area] and two in your chest.
BG is a xxxx of a way to lose weight !
Have fun and win some races !
Jon