Santa Ana winds are caused by strong high pressure over the Great Basin region of the West creating a pressure gradient that amps up winds through the mountains, foothills and sometimes valleys of Southern California. In this case, the winds are getting a major boost from a strong upper-level low pushing southward across the state.

Los Angeles County saw multiple wildfires erupt as "extremely critical fire weather" from dry conditions and Santa Ana winds threatened Southern California into Wednesday, and the National Weather Service warned the worst was yet to come.