When the air is warm and dry, transpiration and evaporation also suck water out of the plants and soil. That leaves dry vegetation that can provide fuel for flying embers to spread wildfires, as the Los Angeles area saw in early January.

Here's a look at the latest maps of the five active Southern California wildfires and what containment means when it comes to fighting fires.

A series of deadly wildfires in Southern California were still burning on Friday, killing at least 10 people and destroying communities, and forcing thousands of evacuations across the region. Arson is expected as the cause of at least one of the fires.

The Hurst Fire has set 505 acres ablaze near San Fernando, California in the Sylmar neighborhood, according to Cal Fire. It is 0% contained. The cause of the fire, which was discovered on Tuesday at around 10:30 p.m., remains under investigation, according to the department.

Utility giant Southern California Edison received "evidence preservation notices" from attorneys representing insurers.

Investigators are considering an array of possible ignition sources for the huge fires that have killed at least 10 people and destroyed thousands of homes and businesses in the Los Angeles area

The Eaton Fire was first reported around 6:30 p.m. local time near the eastern Los Angeles suburb of Altadena, according to KTTV and CBS News. It has since set 1,000 acres ablaze and remains at 0% containment, according to Cal Fire.