Geography of southern California
Despite the popular image of California as a place of sunshine and perfect weather, the local climate can be very diverse, with some areas experiencing more extreme conditions.
Climate is affected by factors such as latitude, topography, and proximity to water masses - primarily the Pacific Ocean, and southern California's mountain ranges.
Essentially, the mountain ranges separate southern California into two distinct climatic regions: The heavy-populated coastal area west of these mountains is the one most associated with the term "southern California" and is characterized by pleasant weather all-year round, without frequent heat spells in the summer and without low temperatures in winter.
Due to the topographic features and proximity to the Pacific, southern California has its share of both low clouds and fog.
This period, known to the locals as "May Gray" and "June Gloom", dims the coastal skies of sunny southern California.
[6] During this time, the coastal clouds may remain all day, but often give way to some hazy afternoon sunshine.
Years with warmer ocean temperatures, influenced by the broader El Niño weather pattern, may result in fewer gray days in June, whereas the cooler ocean temperatures associated with a La Niña pattern, usually foretell more gray days in the season.
[9][10] Hot and extremely dry, they are also known as "Devil winds", and descend on the coastal region from the continental interior of the American West, increasing in temperature as they approach the ocean.
[13] Climate change has also widened the wildfire "season" from a few summer months to virtually the entire year.
Because of this, this area is one of the most geologically active regions in California, with surface changes from fractions of an inch to six feet.
The Ranges create a number of coastal plains and valleys which have become densely populated because of their prime living conditions.
[30] This range starts in the north, in the Corona area heading southeast of the Puente Hills region.
The San Jacinto Mountains are located in the desert areas in the north and east side of southern California.
The range extends for approximately 30 miles (48 km) through Riverside, San Diego and Imperial counties, along the western side of the Coachella Valley, where they bound the Anza-Borrego portion of the Colorado Desert.
[34] The ranges are affected by the marine layer that provides cooling temperatures and fog, and rainfall varies seasonally with tropical storm activity.
