re: Big Bed/Alpine/Marfa/Ft. Davis/Terligua

It'll be damn hot in August. Forget about camping along the Rio Grande, that will probably be well north of 100 degrees every day. Even the Chisos Basin campground will be hot and that is the only place with elevation for camping (around 5,000 ft if I remember right). It's quite a bit cooler than along the Rio Grande but it was still pretty toasty when we camped there a few years ago in May. Nights are nice though, there is almost no humidity. And the stars are the best I've ever seen. There is a hike up Boot Canyon that gets to something like 9,000 feet. The top part is very nice, but no camping there. Honestly, I wouldn't think about tent camping Big Bend in August, and I do love the place.