The Great Basin is an arid region where average annual rainfall is generally less than 10 inches due to its desert-like climate.

The Great Basin is primarily a desert, characterized by its low precipitation levels. This is due to the "rain shadow effect" caused by surrounding mountain ranges like the Sierra Nevada, which block moist air from reaching the region. Most precipitation occurs as snow in higher elevations during the winter months, while lower areas receive minimal rainfall. The lack of significant water sources shapes the unique desert ecosystem of the Great Basin, which includes salt flats, sagebrush, and adapted wildlife species.