The Sonoran Desert is in southwestern Arizona, southeastern California, most of Baja California and the western half of the state of Sonora, Mexico. The Sonoran Desert covers about 100,000 square miles (260,000 sq km).
The Sonoran Desert is rich in plant life with at least 2,000 different species. But two types of plants th distinguish the Sonoran Desert from the other North American deserts. These plants are: legume trees and columnar cacti, particularly saguaro and pipe organ cacti.
Geography: The Sonoran Desert’s location is at latitude 25° to 33° North and longitude 105° to 118° West.
Much of this desert has a bi-seasonal rainfall pattern, though even during the rainy seasons most days are sunny.
In the northwest areas of the Sanoran Desert, storms from North Pacific Ocean occasionally bring widespread, gentle rain from December to March. From July to mid-September, the summer monsoon brings surges of wet tropical air and frequent but localized violent thunderstorms. While there are some mountainous area where frost occurs, most of this desert is frost-free.
The rain and lack of frost provide a perfect environment for saguaro cacti.