The rain is raising concerns about potential mudslides in recent burn scar areas, including Malibu, Altadena, and other regions.

Because of the recent wildfires, parts of Southern California are vulnerable to mudslides, mudflows, and landslides. Ash and debris are created when trees and other objects are burned in wildfires, and this can cause the ground to become slick.

“Recent research shows that debris flows almost always happen in Southern California after wildfires, and given that there are multiple wildfires and each of them is pretty large, really we’re in a situation where the next large rainfall event is almost certain to generate some sort of debris flow.”