 According to the United States Census Bureau, the city has a total area of , all of it land.Maricopa is in the extreme southwestern corner of the San Joaquin Valley, on the first rise of land into the foothills of the Coast Ranges, with the Temblor Range, following the San Andreas Fault, trending northwest of town, and the San Emigdio Mountains to the southeast.The climate of the area is hot and semi-arid, with summertime temperatures routinely exceeding .