Storm raises worries about floods, slides

A storm rolling in from the Gulf of Alaska threatened to dump up to 8 inches of snow on Los Angeles County mountains by early today, while rains farther south raised worries about mudslides and flash floods in fire-scarred canyons.

A snow advisory was issued until 8 a.m. today for mountains higher than 6,500 feet in Los Angeles and Ventura counties.

The warning did not include the Santa Monica Mountains, said Stuart Seto, a weather specialist for the National Weather Service in Oxnard.

The wet weather also threatened to create dangerous conditions in communities that burned in the recent wildfires. Flash-flood watches were in effect for Ventura and Los Angeles counties for much of Tuesday, and a flood watch was issued for Orange County until morning, Seto said.

Forecasters initially expected about half an inch of rain to fall per hour, with much of it hitting Los Angeles at the height of the evening rush-hour commute Tuesday.

By late Tuesday evening, however, .02 inches of rain had fallen at the Santa Monica Airport and .95 of an inch had fallen at Monte Nido, north of Malibu.

With the ground still dry from the October wildfires, “that could start mud and debris flowing,” Seto said.

Concern is particularly high for heavily burned Orange County canyons where hillsides remain denuded of vegetation.

The amount of rain predicted for Orange County was small enough that there were no immediate evacuation plans, said Capt. Mike Blawn of the Orange County Fire Authority.

A hotline was activated Tuesday afternoon by Orange County’s emergency operations center to answer storm-related questions.

Los Angeles County’s average annual rainfall, which is measured from July 1 through June 30, is 15.14 inches, the bulk of which falls during the winter months. So far this year, the county has received a total of 2.45 inches since July compared with an average of 2.79 inches for the period, Seto said.

But compared with last year, a record dry year when the county had received only 1.08 inches by this time, Seto said L.A. could easily get back on pace after this storm.

In Malibu, sandbags and concrete barriers went up weeks ago in areas affected by October’s brush fires to prepare for floods or mudslides, said Brad Davis, the city’s emergency services coordinator.

Sandbags also were available for residents at all city fire stations, he said.

Accidents caused traffic problems throughout the day Tuesday, said Officer Patrick Kimball of the California Highway Patrol.

Officers responded to nearly 200 crashes from midnight to 2 p.m., most attributed to wet conditions. There were 77 during the same period last Tuesday, Kimball said.

In northern L.A. County, a big rig that jackknifed on Interstate 5 south of Weldon Canyon Road blocked the truck lanes for about two hours, a CHP spokesman said.

In Santa Clarita, the CHP shut down two lanes of the 14 Freeway north of Oak Spring Canyon Road for about two hours after a crash that left one person dead.

And on the 5 Freeway at the Hollywood (170) Freeway, all lanes were blocked for about an hour and a half, starting at 8:40 a.m., after a multi-vehicle collision that left four people injured, one critically, fire officials said.

Numerous accidents occurred near freeway ramps, where speeding drivers attempted to stop too late, hydroplaned and lost control, officers said.

“People are taking those a little too fast and they’re braking too late,” said CHP Officer Francisco Villalobos.

paloma.esquivel@latimes.com

Times staff writer Molly Hennessy-Fiske contributed to this report.