In recent days, however, the region’s powerful Santa Ana winds—which have been fanning the flames—have begun to slow down. This lull has offered firefighters a reprieve and a key opportunity to make progress against the blazes, but forecasts suggest the Santa Ana will return next week. What are these gusts, and how have they become so strong?

Helping drive the wildfires in the US city of Los Angeles are the so-called Santa Ana winds, a weather phenomenon known to dry out "the hills and the nerves to flash point."

Red Flag Warnings remain in effect through Friday evening for much of Los Angeles and Ventura Counties, the National Weather Service said.