LOS ANGELES _ Malibu schools are closed and residents in some communities will be forced to evacuate beginning Tuesday morning as Southern California prepares for another day of heavy rain, heightening the threat of mud and debris flows in areas scarred by recent wildfires.
Malibu City Manager Reva Feldman said at Monday night's City Council meeting that her staff will send out a reverse 911 call to residents living in neighborhoods under the mandatory evacuation, which include Corral Canyon, El Nido, Escondido, Old Chimney, Escondido Drive, Latigo Canyon, Malibu West, Trancas Canyon, Malibou Lake, Ramirez Canyon Road and the Paradise Cove Mobile Home Park and Restaurant. Los Angeles County sheriff's officials have also been knocking on doors to alert residents.
Residents near the Woolsey fire burn area who have been notified will be ordered to leave at 8 a.m. The city opened its emergency operations center at 6 a.m. and plans to keep it open 24/7 until the weather passes.
"I urge everybody to please assess your personal situation," Feldman said. "You cannot escape mud flow. You cannot fight it. You need to be very careful and think this through. Please think this through and take care of your family."
The National Weather Service issued a flood advisory for western Los Angeles and Ventura counties, warning that roads, streams and highways could pool with rain through Tuesday night as the latest in a series of strong Pacific storms pounds the region.
Forecasters warn that isolated thunderstorms could accompany Tuesday's storm, likely in the afternoon and evening, which could bring rain down at a faster rate and raise concerns about debris flows.
One of the key elements in determining whether a storm will result in mud or debris flows is the intensity of the precipitation that falls on an area. Other factors include how recent the area burned and the topography, experts say.
The soil in burn areas cannot absorb a lot of moisture, so heavy rainfall can lead to fast-moving runoff containing mud, debris and even trees and boulders. When rain falls over time, it can be gradually absorbed or dispersed, but when areas see rapid runoff, entire hillsides can come down without warning, sometimes with deadly results.
Authorities in Santa Barbara County ordered people who live below the Sherpa, Whittier and Thomas fire burn zones to evacuate by 10 a.m. Tuesday. They said people living next to the evacuation areas, particularly in Montecito, Summerland and Carpinteria, could be stranded if debris flows damage or block roads.
"Residents in these adjacent areas should be prepared for this possibility and consider leaving the area during the evacuation," authorities said in an alert.
In Riverside County, authorities ordered residents to evacuate communities near the Holy fire burn area in Riverside County, citing the potential for dangerous debris flows, but downgraded the evacuation order to voluntary late Monday.
Monday's storm dumped rain and snow across Southern California, set new rainfall records in Burbank and Sandberg _ a town near the Grapevine _ and sent mud sliding across Pacific Coast Highway just south of Leo Carrillo State Beach. A river of mud eventually closed Pacific Coast Highway from Trancas Canyon Road and Broad Beach Road in Malibu to Las Posas Road in Ventura County for several hours before the road reopened about 4 p.m.
During a storm earlier this month, a shallow mudslide covered a stretch of PCH in Malibu and trapped some cars.
A 250-foot mud flow also damaged an Encino home and swept its guesthouse off its foundation Monday evening. Three people inside escaped without injuries, and officials issued a voluntary evacuation order for 14 homes potentially in a slide zone in the area.
