As a former Zonie, Arizonan, I advise drinking lots of water. Before you start out tank up as much as you can and drink more as you go along. You can't drink too much water.
And forget drinking beer, wine or any other booze while you are out in the heat. Save it for when you are in a nice cool place.
I had heat stroke once it was not fun at all, ended up spending a night in the hospital.
It was 100*F yesterday in Tracy Ca. My wife and I put 11 miles on our bikes. For me, 9 on a road bike and 2 on a MTB.
My brother-in-law says that the sweat is about 10 feet in back of you while you are moving down the road. It catches up at stop lights.
Joe