LOS ANGELES (CBSLA.com) — Rain accompanied by strong winds drenched the Southland Tuesday, raising the risk of flash flooding in much of the region and mudslides in neighborhoods below hillsides denuded by wildfires.

A flash-flood watch went into effect at 8 a.m. and will remain in force through late Tuesday night over a wide area that includes beach cities, metropolitan Los Angeles, the Hollywood Hills, L.A. County Mountains, Santa Catalina Island and the San Fernando, Santa Clarita, San Gabriel and Antelope valleys, as well as areas in Ventura and Santa Barbara counties. In Orange County, the watch took effect at 9 a.m.

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The rain, along with gusty winds, is the result of a Pacific storm system. Forecasters said the storm should drop about 1 to 2 inches of rain along the coast and in valley areas, and 2 to 5 inches in the mountains and foothills.

Rainfall rates of around a half-inch per hour are expected “possibly for several hours, which could produce dangerous flash flooding, with damaging mud and debris flows,” according to a National Weather Service statement.

“While all recent burn areas will be threatened, areas especially at risk include the Springs, Colby, Powerhouse and Williams burn areas.”

City officials in Glendora have been warning residents near the Colby Fire burn area to prepare for possible mudslides and debris flows. The alert issued by the city requires residents to remove vehicles, trash bins and other obstructions from the street to ensure emergency crews can access the area and to prevent any damage from mudflows.

The Glendora alert level, which had been at yellow, was raised to orange at 6 a.m., urging residents to voluntarily evacuate areas endangered by flooding and debris. An evacuation center was set up at the Crowther Teen & Family Center, 241 W. Dawson Ave. The Inland Valley Humane Society is available at the center to offer assistance with pets. Horses can be taken to the Pomona Fairplex, 1101 W. McKinley Ave.

The affected burn area is generally described as the area north of Sierra Madre Avenue between the western city limits to the eastern boundary of properties on the west side of the Little Dalton Wash.

Glendora officials said late this morning that roughly 18,000 sandbags had been distributed to residents in the past 48 hours, and more are available. No mud or flooding issues had been reported by midday in the area, but Glendora officials said the heaviest rain was expected this afternoon and into tonight, with as much as 3 inches of rain possible.

Glendora Mountain Road was closed, and city officials said the route will remain blocked until further notice.

In the fire-scarred areas of Silverado Canyon in Orange County, residents were also preparing for possible mud flows. Emergency officials issued a warning to residents and even suggested voluntary evacuations beginning at 7 a.m. They said Silverado Canyon Road could potentially be closed.

Residents in the 40 to 50 homes from 30311 Silverado Canyon Road to the end of the canyon were advised even before Tuesday’s rains began in earnest to evacuate, Orange County Sheriff’s Department Lt. Jeff Hallock said.

“This is one of those communities, where when something like this happens, there are a certain amount of us that stay here and kind of watch out for the rest of the neighborhood,” Danny Wilson, a Silverado Canyon resident, told KCAL9’s Brittney Hopper.

Doug Green, another resident, said: “Now we’re experiencing something that they’ve never experienced here, which is no vegetation on the hillsides and so because of that, we don’t know what to expect.”

All day and into the night, Orange County Fire Authority firefighters filled sandbags for residents.

Some cities, including Fullerton, Mission Viejo and Costa Mesa, are providing residents with free sandbags to help them protect their properties. Sand and sandbags were also made available at Los Angeles Fire Department stations. Burbank officials are offering residents sandbags at the Public Works Field Services Yard at 124 S. Lake St.

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In Long Beach, city crews worked to clear catch-basins, test pump stations and fortify sand berms on beaches. The city also installed booms to prevent debris from flowing into marina areas, and deployed additional staff such as swift-water rescue teams to quickly respond to emergency situations.

In the San Fernando Valley, LAPD’s West Valley division advised motorists to avoid streets around the Sepulveda Basin, including westbound Burbank Boulevard from the 405 Freeway, Hayvenhurst and Burbank, Woodley and Victory, and Balboa and Burbank. Streets around the Sepulveda Basin are prone to flooding during heavy rain.

A wind advisory will be in effect in the San Gabriel mountains in Los Angeles and Ventura counties from 2 p.m. Tuesday until 3 a.m. Wednesday. Southeast-to-south winds of 25 to 35 mph with 50-mph gusts are expected in the mountains, mainly above 5,000 feet, according to the NWS.

The wind could prove to be a problem for motorists on Interstate 5 in the area of The Grapevine, and on Angeles Crest Highway, especially for the drivers of high-profile vehicles and vehicles towing trailers, according to an NWS statement.

In the Inland Empire, residents are stocking up on supplies and taking necessary precautions.

“You always make sure you have emergency supplies at the house. You have flashlights, food that you can heat up if the electricity goes out, candles,” Lytle Creek resident Cathleen Coakley said.

“We got a first aid kit, a battery jumper, a full tool set,” Dan King added.

In Redlands, residents filled up sandbags as the storm approached, knowing unstable rocks and dirt can quickly turn into a devastating mudslide.

“Last time we had the rain the water came down real heavy,” Eddie Butler said.

On the roads dozens of crashes were blamed on the weather, including multiple collisions in the Cajon Pass.

In downtown Riverside along the 91 Freeway, visibility was poor. And in Devore, a pick-up truck driver lost control and landed on top of a no parking sign and a fence along the 215.

“I was coming around the turn to fast and I hydroplaned and into the fence I went,” the driver said.

Showers are expected to continue tonight and into Wednesday, according to the NWS. The area is expected to slowly dry out as the week wears on.

The Los Angeles County Department of Public Health warned beach goers to avoid storm discharge areas due to debris and bacteria.

COMPLETE COVERAGE:

Bad Weather Leads To More Than 100 Delayed Flights At LAX
Downed Power Lines Force Closure Of PCH Through Pacific Palisades
Flooding Prompts Evacuations In Camarillo Springs
PCH Closed Indefinitely Due To Mud Slide, Storm

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