The climate of the mountains is a Mediterranean climate. Summers are mostly dry except for occasional thunderstorms, and winters comparatively cold and wet. Snowfall is infrequent due to the relatively low elevations of mountains within this ridge, with only the few tallest peaks regularly receiving snowfall during the winter.
Ecology
Mainly the ridge falls under the California montane chaparral and woodlands ecoregion, excepting the northeastern flank's gradual slope into the Antelope Valley near Palmdale where the ecology transitions to that of the Mojave Desert. The mountains are primarily covered in short grasses, scrub oak trees, yucca, and other chaparral shrubs. The ridge is prone to wildfires in the summer and fall, especially when the Santa Ana winds blow in from the Antelope Valley.
Hydrology
Aerial view of the Sierra Pelona Mountains and San Andreas Fault
The San Francisquito Canyon, which runs north-south through the mountains, served as a major wagon route between the Antelope and San Fernando Valleys. This corridor summited at San Francisquito Pass and was part of the El Camino Viejo - an alternate land route to the El Camino Real for reaching northern Spanish and Mexican colonial Alta California - as well as the Butterfield Overland Mail route.
20th century
The Ridge Route, a landmark two-lane highway that connected Los Angeles to the rest of California, was built along the western flank of the ridge and was completed in 1915. It was later bypassed by the Ridge Route Alternate (US 99) in 1930, itself superseded by Interstate 5 completed in 1971.
