With the strongest gusts expected on Tuesday, extreme fire condition threats will prevail until midweek, L.A.-area fire chiefs say.

After a brief break on Sunday afternoon, another prolonged round of gusty Santa Ana winds is expected to develop, forecasters say.

Dangerous Santa Ana winds are returning to Southern California, and that has forecasters and fire officials concerned that any new or existing fires could spread rapidly and display erratic behavior.

Santa Ana winds occur when air flows west from a region of high pressure over the dry Great Basin to lower pressure off the California coast, According to Accuweather. As that cool interior air flows over and through mountain passes, it accelerates, sinks and compresses.

Another wave of Santa Ana winds arrive Saturday, likely generating gusts over 40 mph throughout the Inland Empire going into Sunday.

Santa Ana winds in Southern California are often-fierce winds that topple power lines and trees and can turn a spark into a raging wildfire.

By the time the winds get to the point where the Eaton Fire broke out in Altadena on Jan. 7, it’s not uncommon for them to have less than 5 percent relative humidity, meaning essentially no moisture at all.

The Palisades, Eaton, and Hurst fires covered more than 5,600 acres of Southern California as of Wednesday morning. Tens of thousands were under mandatory evacuation orders but the fires increased in size overnight, helped by the blustery Santa Ana winds.