In the far eastern part of the state the Chihuahuan Desert dominates due to low precipitation and extremely high temperatures; some areas of the eastern part of the state are so dry no vegetation is found like the Sand Dunes of Samalayuca. There are two distinctive climate zones found in the eastern part of the state: Hot Desert (BWh) and Cool Desert (BWk) which are differentiated by average annual temperature due to differences in elevation. There is a transition zone in the middle of the state between the two extremely different climates from the east and west; this zone is the Steppe characterized by a compromise between juxtaposed climate zones.