January: West Texas winter is ideal: warm afternoons on the desert floor, crisp nights in the Chisos, and the Rio Grande canyons comfortable to explore. Big Bend has some of the darkest skies in the Lower 48.
February: Temperatures are close to perfect for the long trails: Emory Peak and the South Rim are comfortable, and the desert floor rarely tops the 70s.
March: Texas bluebonnets and cactus blooms paint the lower desert, and the Rio Grande canyons are still comfortable before May's heat.
November: Heat is gone, crowds haven't arrived for the holidays, and the desert is often green after late-summer rains.
Permits and reservations
No reservation is needed to enter the park.
Campgrounds: All park campgrounds require reservations. The busy season is October through April, when sites are often fully booked.
Backcountry & roadside campsites: A backcountry permit ($10 per night) is required for all backcountry camping, and you choose your sites when it is issued. Many Chisos and roadside sites can be reserved online on Recreation.gov up to about 6 months ahead.