Outbreaks of heavy rain are causing concern in burned areas; a flash flood warning has been issued

A flash flood warning for the Franklin fire scar and part of the Palisades fire area has been canceled. The warning, the National Weather Service’s highest warning level for possible flooding, was issued at 7:40 p.m. Sunday as the storm in Southern California intensified.

Radar and rain gauges indicated that the thunderstorm was “producing heavy rain throughout the warning area,” including Malibu; Malibu Creek State Park, near Calabasas; and Malibu Canyon and Las Virgenes roads through the Santa Monica Mountains. The warning was issued around 10 p.m

Flows of mud, rocks and debris, which forecasters say could disrupt roads and homes in and below the burned areas, continue to be a problem through Monday as heavy, localized rain is possible.

A rainfall rate of 0.39 inches per hour was reported near Pepperdine University around 8:15 p.m., the weather service said. A rate of half an inch per hour or more is the point at which debris flows could begin in the burned areas, forecasters said.

Debris flows can occur when the water goes down quickly and, apart from the mud, it picks up stones, branches and sometimes rocks – something that can damage cars and houses. It can be life threatening.

Reports of mudslides and debris flows trickled in Sunday evening. Pacific Palisades city hall officials said the Los Angeles Fire Department was busy clearing the mud that had piled up on Palisades Drive Sunday evening and that black water with ash had reached the ocean. ABC7 Eyewitness News filmed residents working to free cars stuck in mud buildings in Woodland Hills.

Just before 5 p.m., Caltrans announced a mudslide in Topanga Canyon has closed a portion of the Pacific Coast Highway. At 8:15 p.m., flooding was reported on the highway, the ministry said.

At 8 p.m., the Santa Monica-Malibu Unified School District announced that it will close all four of its Malibu schools on Monday due to hazardous road conditions and school access challenges.

A flash flood watch, the lowest level warning, remained in effect Sunday night for areas burned by the Eaton fire in the Altadena and Pasadena areas; the Palisades and Franklin fires in the Pacific Palisades and Malibu areas; the Hughes fire around Lake Castaic; and the Bridge fire in the San Gabriel Mountains west and southwest of Wrightwood.

As the storm brought heavy, localized rain Sunday, the weather service issued temporary high-level flood advisories for large areas of Southern California, indicating that flooding is present, imminent or possible.

Between 6 and 11 p.m., the service issued multiple advisories for LA, Santa Barbara and Ventura, covering the Palisades, Franklin, Kenneth and Mountain burn scars. Most would expire at midnight or earlier.