LOS ANGELES (CBSLA.com/AP) Residents across Southern California Wednesday braced for a third rainstorm of the season.

According to the National Weather Service, strong winds and moderate to heavy rainfall with a chance for thunderstorms is expected throughout the day.

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A flash flood warning for the Calgrove burn area of northwestern Los Angeles County will remain in effect until 2 p.m., forecasters said.

The heaviest rainfall is expected to occur between 10 a.m. and 4 p.m., triggering between a half-inch and an inch of rain per hour, meteorologists added.

A severe thunderstorm warning was in force for northwestern Los Angeles County and northeastern Ventura County until 11 a.m., the National Weather Service reported.

Forecasters said a severe thunderstorm that appeared on radar near Fillmore was capable of producing damaging winds in excess of 60 mph and moved east at 35 mph. Penny-sized hail and damaging winds may have been seen in Thousand Oaks, Simi Valley, Chatsworth, Woodland Hills, Canoga Park, Calabasas, Moorpark, Oak Park, Lake Piru, Somis, Piru and Winnetka.

A wind advisory will remain in effect until 9 p.m. for the Santa Monica Mountains Recreational area and the Santa Clarita Valley, the National Weather Service said.

The strongest winds could reach up to 60 mph in the mountains and Antelope Valley.

Forecasters said the combination of strong winds and heavy rainfall may down trees and power lines across Southern California.

Shortly before 11 a.m., officers shut down the off ramp of the northbound 101 Freeway at State Beaches due to debris flow.

Authorities have also warned the public to avoid traveling on roadways in north Ventura County due to heavy rainfall.

Meanwhile, residents living in Camarillo Springs prepared for voluntary evacuations this morning. Authorities said the evacuations could be upgraded to mandatory status depending on the severity of the storm.

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Six Flags Magic Mountain and Knott’s Berry Farm theme parks will be closed today due to inclement weather, City News Service reported. Disneyland and Universal Studios will remain open for business.

According to the Ventura Police Department, Harbor Boulevard between Sanjon Road and the pier will remain closed until further notice due to flooding in the area.

In total, between 2 and 3.5 inches of rain is predicted to fall across the coastal and valley areas, and up to 5 inches falling in the mountains.

As of 9 a.m., 600 Los Angeles Department of Water and Power customers and 3,500 Southern California Edison customers were without power as a result of the storm. At this time, it remains unclear when power will be completely restored.

On Tuesday, flash flooding and flows of mud and debris were a concern, especially in places left barren by last year’s wildfires. Residents of the Silverado Canyon burn area in Orange County and the Solimar burn area in Ventura County were urged to consider evacuating.

In Orange County, a homeless man in his 40s was swept off his feet by swift waters and washed nearly a mile down Brea Creek in Buena Park before he pulled himself out, county fire Capt. Steve Concialdi said. He was treated at a hospital for scraped feet and arms.

Rocks fell on the roadway through Malibu Canyon, damaging four vehicles and clogging a heavily traveled commuter route through the steep Santa Monica Mountains, and Los Angeles police were rousting the homeless from normally dry riverbeds.

As steady and sometimes heavy rains fell, Garcetti urged people to clear gutters and anything in their yards that might clog storm drains, and to stockpile sandbags if their home is susceptible to flooding.

Garcetti also said that the city’s homeless encampments have been mapped for the first time, and he promised shuttles to bring people to shelters with 6,000 beds.

Los Angeles Fire Chief Ralph Terrazas said swift-water rescue teams were ready to be deployed if they were needed.

The storms whipped up large ocean swells that generated hazardous breaking waves at west-facing harbors. Ventura’s Harbor Boulevard was closed Tuesday by flooding about a foot deep, police there said.

The current El Nino — a natural warming of the central Pacific Ocean that interacts with the atmosphere and changes weather worldwide — has tied 1997-1998 as the strongest on record, the National Oceanic and Atmospheric Administration’s Climate Prediction Center said, citing statistics that go back to 1950.

El Ninos usually bring heavy rains to California, although it remains to be seen whether people should expect anything like a repeat of 1997 and 1998, when storms killed 17 people, wiped out crops, washed out highways and pushed houses down hillsides.

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