The area's first settlers were Native American Tribes, whose descendants occupy the Cocopah and Quechan reservations near the city. In 1540, expeditions under Hernando de Alarcon and Melchior Diaz visited here and immediately saw the natural crossing of the Colorado River was an ideal spot for a city.
From the 1850s through the 1870s, the Yuma Crossing was known for its steamboat crossing, and spot for them to stop on the way up and down the river. The steamboats transported passengers and equipment for the various mines and military outposts. Yuma served as the gateway to the new western territory of California, as it was one of the few natural spots to cross the very wide Colorado River. The Southern Pacific Railroad bridged the river in 1870 and helped continue Yuma as a major hub in the desert southwest. Yuma became the county seat for the area in 1864. Famous farm labor organizer Cesar Chavez was born and spent much of his life in Yuma.
In 1997, the desert city sustained a full tropical storm after Hurricane Nora made landfall at the mouth of the Colorado River and quickly moved due north along it. The extraordinarily rare event cut power to 12,000 customers in Yuma, and dropped 3.59 inches or over 90mm of rain at Marine Corps Air Station Yuma.
During the summer, temperatures can reach upwards of 120 degrees. The heat index has been known to travel above 140 degrees due to the areas high humidity because of all the farmland that exists. The winters are mild, with daytime highs reaching into the 70s. The main thoroughfares through Yuma are Interstate 8, which runs east and west from south Phoenix to San Diego, and U.S. 95, which runs north and south from Canada to Mexico. Situated on the western edge of the Sonoran Desert, Yuma still has attracted approximately 120,000 year-round residents, as well as another 60,000 snowbirds (winter visitors who leave their cold northern homes).