Sierra Madre Occidental Sierra Madre Occidental The Sierra Madre Occidental is a major mountain range system of the North American Cordillera, that runs northwest–southeast through Northwestern and Western Mexico, and along the Gulf of California. The Sierra Madre is part of the American Cordillera, a chain of mountain ranges (cordillera) that consists of an almost continuous sequence of mountain ranges that form the western "backbone" of North America, Central America, South America and Antarctica. The Spanish name "sierra madre" means "mother mountains" and "occidental" means "western" in English, with these being the "Western Mother Mountains". To the east, from the Spanish "oriental" meaning
Transverse Ranges are at high elevations, with Cajon Pass being at a modest 4,190 ft (1,277 m) above mean sea level; this means that snow is less of a factor here than in the moderate to high mountain passes to the north like Donner Pass. Still sometimes, heavy snowfall can snarl traffic on Tejon and Cajon Pass, the higher two of the three freeway passes. I-5 and I-15 commonly experience heavy traffic over their mountainous route across these mountains. Transverse Ranges The Transverse Ranges are a group of mountain ranges of southern California, in the Pacific Coast Ranges physiographic region in North