The Santa Ana winds (named for a canyon in Southern California) are abrupt bursts of dry, hot air blowing into the Los Angeles region from the deserts of the Great Basin to the northeast.

When a high-pressure system forms over the deserts to California’s east, it pushes air toward the Pacific coast. As they move down the Santa Ana and Sierra Nevada mountains and shoot through ...

In recent days, however, the region’s powerful Santa Ana winds—which have been fanning the flames—have begun to slow down.

Extreme fire weather returns to Southern California - particularly Los Angeles and Ventura counties - as winds of up to 100 mph have prompted the most urgent warning from the National Weather Service.