Petrified Forest National Park is a semi-arid grassland with long-known wonders as well as newer opportunities for exploration, including backcountry hikes into areas previously closed such as Red Basin and little known places like Martha's Butte, along with new exhibits. Temperatures range from above 100° F (38° C) to well below freezing, and about 10 inches (25.4 cm) of moisture comes through infrequent winter snow and often dramatic summer thunderstorms. Its animals and plants are adapted to these extremes in temperature and moisture.