Southern California's Notorious Santa Ana Winds: A Symbol of Mother Nature's Ferocity!

The Santa Ana winds are a well-known facet of Southern California life. In addition to traffic, smog, earthquakes and fires, the Santa Ana winds are right up there in the pantheon of Southern California ills. A seasonal-type of wind, Santa Ana winds roar through the canyon and mountain passes of Southern California in Fall and early Spring, sometimes with hurricane force, and are notorious for toppling trees and power lines, blowing roofs off of houses, and overturning big rigs and other high-profile vehicles. But what causes Santa Ana winds and why are they so powerful?

The Santa Ana winds are caused by strong high pressure weather systems that situate themselves over the Great Basin area of the western United States - the area between the Sierra Nevada and the Rocky Mountains - a giant desert area. When a strong high pressure system is in place over the Great Basin, the winds spin around the center of the high in a clockwise fashion. These winds, by virtue of their location in the arid Great Basin, are dry and warm to begin with, and as these winds blow in a clockwise direction towards Southern California, they blow across the large Mojave Desert, where they heat up even further and compress as they descend in elevation, which increases their wind velocity. As these winds continue to blow towards Southern California, they are funneled through the numerous passes and canyons separating the Los Angeles Basin from the desert areas, a form of compression that drastically increases their velocity. As these winds blow toward the low-lying areas of Southern California, they again drop in elevation which further increases their temperature and wind speed. So, by the time these Santa Ana winds reach Southern California, they are blowing with a raging ferocity that puts Southern California on edge.

The Santa Ana winds, in addition to causing widespread structural damage and overturned cars and trucks, are a tremendous Southern California fire hazard. When these dry, hot, and fast winds come barreling across Southern California, the region's humidity levels plummet; the areas vegetation and hillsides are swept dry of any residual moisture; the brush and vegetation are left parched and brittle and are extremely vulnerable to ignite at the slightest provocation. And, to make matters worse, when a fire does break out in the middle of a Santa Ana wind condition, the strong winds and frequent gusts, which are notorious for suddenly changing direction, tend to fan the flames and spread the fire over large areas. It's common to see flames blown across roads and highways and smoldering embers being blown for miles before they settle and ignite a new blaze. The speed of the Santa Ana winds and their unpredictability make them a grave fire danger. As a result, the Santa Ana winds are a firefighters' worst nightmare in Southern California.

However, for all the negativity associated with the Santa Ana winds, they are responsible for one obvious benefit: clean air! On days when the Santa Ana winds are blowing - and when there are no fires spouting smoke into the air - the air in Southern California is pristine. Visibility extends for miles and miles, and distant landmarks and mountain peaks, normally obscured by a murky, brown haze wafting through the air, appear close enough to reach out and touch. And off the coast, Santa Catalina Island, twenty-six miles from the Long Beach shoreline, appears as a dramatic, up-close backdrop to the waters of the Pacific Ocean. No matter what the end result of a Santa Ana wind condition might be; a raging fire, property and structural damage, flying debris, or just a wind-swept pristine skyline, it's impossible for Southern Californian's not to notice when the Santa Ana's come blowing in to town!