Devil Winds

“There was a desert wind blowing that night. It was one of those hot, dry Santa Anas that come down through the mountain passes and curl your hair and make your nerves jump and your skin itch. On nights like that every booze party ends in a fight. Meek little wives feel the edge of the carving knife and study their husbands’ necks. Anything can happen.”-Raymond Chandler-”Red Wind.”

The Southland is experiencing its first Santa Ana of the season. Although winds have been lighter than is often the case with this weather pattern, the hot, dry gusts have fanned scattered fires in tinder-dry areas and sent Southern Californians back to the beach.

The winds have spread many disastrous fires, including the 1961 Bel-Air fire that destroyed hundreds of homes. Fire officials estimate that fires pushed by Santa Anas spread five to six times faster than other brush fires.

This regional phenomenon lasts through autumn and sometimes into winter, knocking out power, tripping burglar alarms and sending tumbleweeds hurtling across freeways. Santa Ana conditions begin hundreds of miles from Southern California and are generally strongest in the Riverside-San Bernardino area.

The topography and position of the Southland put it on target for the hot, dry winds that begin in a high-pressure system over Utah and snake through mountains and deserts on their way to the ocean.

It’s said people act strange during Santa Anas. As Joan Didion put it: “It is the season of suicide and divorce and prickly dread, whenever the wind blows.”

Flowing From Desert to Mountain to Sea Santa Ana winds move through the mountains from the north-northeast, funneling through the canyons into the basin. The heat of the wind is more the result of its downhill motion than its movement across the desert. 1. Air is cool and holds fair amount of moisture. 2. Air loses moisture as it moves up mountains. 3. Wind speed increases as air funnels through mountain passes. 4. Air temperature increases 5.5 degrees for every 1,000 feet it descends. 5. Air that passes over and through mountains has lost almost all moisture.

Tracking the Wind Dry cold fronts passing through the Great Basin states are followed by a high-pressure system that is centered over the Utah-Nevada border, creating westerly winds that eventually become Santa Anas.

Where the Name Comes From There are many theories as to why the winds are called Santa Anas. Some believe the name comes from Satanas, Spanish for Satan. But it is generally accepted that they are named for Santa Ana Canyon, the narrow gap in the Santa Ana Mountains in Orange and Riverside counties, where the winds are especially strong.

More Hot Air Like the Santa Anas, other hot, dry winds occur elsewhere in the world. Chinook: Named after an American Indian word meaning: “snow eater,” the Chinooks blow east of the Rocky Mountains and are common in Denver. Foehn: Occuring in the Alps, they blow in winter when warm air over the mountains is forced to descend. Khamsin: Originating in Egypt and moving eastward into the Middle East, these winds remain hot and dry because they do not cross a vast expanse of water. Siocco: Hot, dusty winds from the Sahara, siroccos form ahead of cyclones moving eastward across North Africa and the southern Mediterranean in the spring. They cool as they cross the Mediterranean and can bring rain and fog to southern Europe. Sources: National Weather Service, UCLA Atmospheric Science Dept., Encylopedia Americana, Weather of Southern California