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LOS ANGELES (CNS) - A pair of storm systems are expected to dump rain on Southern California beginning Tuesday, again raising fears of possible debris or mud flows in recent burn areas.
The first system is scheduled to arrive sometime Tuesday evening, although the brunt of the rain from that storm is expected to fall in San Luis Obispo and Santa Barbara counties, according to the National Weather Service. But Los Angeles and Ventura counties will still see rainfall, likely receiving one-quarter to three-quarters of inch in most areas, but as much as 1.5 inches in "favored hills and mountains, which includes the Palisades and Eaton burn scars."
"This will generally be a beneficial rain for the region," according to the NWS. "Snow levels will be very high and above any major roads. The risk for burn scar debris flows is very small. Flooding impacts should be minor and confined to localized roads and clogged storm drains. ... While the winds will be gusty at times, especially off the Central Coast and in the mountains, the risk for damage is small. LAX may see some east winds however, which will cause some delays."
A second storm system is projected to drop more rain from Thursday afternoon into Friday morning. Although rainfall totals were still being calculated, forecasters estimated that most areas would see a quarter-inch to an inch from that system, with as much as 2 inches falling in favored hills and mountains.
"Again, this will likely be another round of beneficial rain," according to the NWS.
The rain is expected to wind down in the L.A. area by Friday afternoon.
Due to the anticipated precipitation, Caltrans announced late Monday that it will shut down Pacific Coast Highway at 3 p.m. Tuesday between Chautauqua Boulevard in Los Angeles and Carbon Beach Terrace in Malibu. The road is expected to remain closed until at least Friday.
"Out of an abundance of caution, the highway must be closed due to soft soils on both the hill and ocean sides of the road," according to a statement from Caltrans. "Mud and debris flows may occur and canyons may overtop, blocking the road or causing further damage."
Only essential workers -- such as first responders, recovery agencies and utility companies -- will be able to access PCH in the closure area, according to Caltrans.
Residents with passes will still be able to return to their homes in Pacific Palisades via Chautauqua, according to Caltrans.
PCH had just reopened Monday with one lane of traffic in both directions between Santa Monica and Malibu, a stretch that was largely closed since Jan. 7 due to the Palisades Fire.
In advance of the rain, the Los Angeles County Department of Public Works was working to clean drainage facilities and debris basins, install additional k-rails near homes and provide sandbags at vulnerable sites.
County officials updated the public on the preparedness efforts at a Sunday morning news conference in Malibu.
"Los Angeles County has been working around the clock to prepare for this storm, clearing debris basins, reinforcing infrastructure, and making sure our residents have the resources they need to stay safe," said Supervisor Lindsey Horvath, whose Third District includes the Palisades Fire area. "I want to thank all of our emergency response teams for their tireless work to protect our communities. I urge all residents to take this time to prepare -- secure your property, use sandbags where needed, and stay informed as the storm approaches."
County storm preparedness actions include:
-- Debris Basin and Flood Control Maintenance. Public Works crews have been clearing storm drains, catch basins, and debris basins in vulnerable burn areas, removing over 400 cubic yards of mud and debris in Sunset Mesa alone.
-- Infrastructure Reinforcements. With support from the California Office of Emergency Services, the county has deployed 679 feet of k-rail and over 1,500 sandbags in key locations within the Palisades and Eaton burn areas to slow runoff and prevent dangerous debris flows.
-- Beach and Water Quality Protection. The county is actively working with beaches and harbors, the Department of Public Health, and state and federal agencies to prevent post-fire debris from polluting local beaches and coastal waters.
-- Community Resources and Support. Free sandbags and flood risk assessments remain available to residents at designated locations, including the La Costa Post Office at 21229 PCH in Malibu.
Residents were urged to clear drainage paths around their properties, install sandbags to direct runoff away from homes, avoid travel in burn areas and mountain roads during heavy rainfall and sign up for emergency alerts at ready.lacounty.gov.
Los Angeles County experienced its first significant winter storm in late January. The L.A. Basin saw accumulations ranging from half an inch to 1.5 inches, while downtown Los Angeles recorded a total of 0.54 inches of rain.
Although the storm spared recent burn areas in Pacific Palisades and Altadena from the heaviest rainfall, it still caused issues. There were reports last Monday of minor mud flows brought on by the rain, including a slide that closed Topanga Canyon Boulevard at Pacific Coast Highway. Lingering snowfall also forced a roughly 11-hour closure Monday of the Grapevine stretch of the Golden State (5) Freeway in northern Los Angeles and southern Kern counties.
The NWS said the upcoming storm will see snow levels at or above 8,000 feet.
Daytime temperatures are expected to cool significantly, with highs dropping to the lower to mid-60s on Tuesday and near 60 by Wednesday.