>>827021I spent a few days in Big Bend last June. Even then it was hotter than Satan's ballsack so I can't image August. You'd be much more comfortable in the Fall.
We did a night of camping at Chisos basin which is pretty and has most of the trail heads, then a night at the Rio Grande Village campground and crossed (legally) into Boquillas, Mexico for tacos and tequila. It's a shit town but an adventure. You need a passport