Santa Ana Winds

Wildfires burning across Southern California draw much of their strength from the fiercely hot and dry winds known as the Santa Anas.

Santa Ana winds are formed when a high pressure area forms over the Great Basin, the vast expanse of desert that covers much of Nevada, Utah and southern Idaho.

That forces cool, dry desert air toward the southwest. There, the winds plunge down through the mountains of Southern California, channeled by steep terrain toward areas of comparatively lower pressure.

As the winds whistle through canyons and valleys of the mountains that separate the desert from the coastal strip between San Diego and Santa Barbara, the air is compressed and heated as it descends, sometimes dramatically.

The winds dry out vegetation and sap the air of humidity, creating the potential for destructive fires.

Last modified: Friday, 07-Mar-2008 20:56:21 UTC