LOS ANGELES >> The second round of a fall storm dumped snow and rain that jammed traffic on Southern California highways and loosened hillsides in wildfire burn areas today.

At least one vehicle got stuck in a mudslide that shut down Pacific Coast Highway and surrounding roads in and around Malibu neighborhoods charred by last month’s destructive fire.

Kirby Kotler and his neighbors spent days before the storm stacking some 18,000 sandbags behind their homes along the highway — only to see mud, water and rocks blow through the line of defense and across their properties. He wielded water hoses to beat back the flames in November. On Thursday, he used a tractor to keep the debris flow from entering his home.

“Saving my house once again,” said Kotler, 57, a lifelong Malibu resident. “I’m more than a little concerned. If we get another blast of heavy rain there’ll be no stopping the hill from coming down.”

Nobody was hurt when a Southwest Airlines plane from Oakland skidded off a wet runway as it landed during downpours at Hollywood Burbank Airport north of Los Angeles. The plane came to a stop in a graded area designed to slow aircraft that overshoot the runway, the Federal Aviation Administration said.

“As we landed you could feel the brakes,” passenger Grant Palmer told KABC-TV. “Then I started noticing the plane going sideways.”

Palmer said he was prepared to tuck into an emergency posture, but his unflappable co-worker continued writing emails during the rough landing.

Cars and trucks slid in lanes amid heavy snow that forced the closure of Interstate 5 in the Grapevine area between Los Angeles and the San Joaquin Valley. The hours-long shutdown along the key north-south route caused backups for miles, transportation officials said.

The road reopened in the afternoon.

Motorists were urged to use caution on mountain passes, where up to 6 feet (1.8 meters) of snow was predicted at higher elevations.

Mandatory evacuations were ordered for Trabuco Canyon in the Santa Ana Mountains south of Los Angeles and for Lake Elsinore areas in Riverside County. Both were burned in a massive wildfire earlier this year. The National Weather Service extended flood warnings for Orange County even as advisories in Los Angeles and Ventura counties expired.

The system dumped rain that flooded highways and caused nightmare traffic conditions for commuters. A portion of southbound State Route 170 in Los Angeles was shut down after mud flowed onto the roadway. Firefighters rescued motorists from cars stuck in a flooded intersection in the city’s North Hollywood area.

Rocks and debris flowed through a Malibu canyon community that saw homes burned in November and mudslides during thunderstorms last week. City officials reported no injuries and no major property damage. No evacuation orders were issued.

The National Weather Service extended flood warnings and advisories into late morning as the storm intensified, dropping up to 1/3 of an inch (.85 centimeters) of rain in a half-hour in some areas. Meteorologist Keily Delerme said shifting winds allowed more rain to fall.

“We’re seeing some pretty strong showers coming in from offshore, especially compared to Wednesday,” Delerme said.

The system was expected to linger for much of the day before dissipating early Friday.