You can get into trouble fast if the heat jumps up while your riding.

Did a tour two years ago in The Big Bend, Texas.
We set up the tents then,
Decided to ride to the Rio Grande River, just 18 miles away.
Drank one bottle every 6 miles.
One rider crashed, we had a sag car that saved us.
None of us were able to ride the bikes back to the camp site.