At least three people have died in the historic flooding battering California, as multi-million-dollar mansions are trashed by rivers of flowing mud and boulders - while forecasters predict more rain is still to come. The Pineapple Express, a weather system lingering over much of the Golden State, is causing chaos over several regions including the star-studded Beverly Hills, Malibu and Montecito neighborhoods.

The severe weather system has killed three Californians so far and 38 million people remain under flood alerts, as the National Weather Service forecasts additional rainfall of up to six inches into Tuesday. Forecasters estimate a slow-moving and narrow axis of anomalous moisture will continue to focus across Southern California over the next 12 to 24 hours, maintaining a significant threat for life-threatening flash flooding. Chad Ensey, 41, died in his home in Sacramento County on Sunday when a fell on him during the storm, reported NBC News.

It comes as 82-year-old David Gomes died after he was struck by a large redwood tree in Yuba City, northern California, on Sunday night, per ABC10 . An unidentified resident of Boulder Creek, California, died from injuries sustained after a tree fell into their home on Sunday. An atmospheric river brought gusty winds to the Bay Area and Central Coast on Sunday, with the strongest winds in the Coastal Mountains, according to the National Weather Service.

The chief operating officer of California utility Pacific Gas & Electric said Sunday was one of the most damaging single-day storms on record in terms of outages. About 2.5 million people in the Los Angeles area, including the Hollywood Hills and Beverly Hills, have already accumulated up to nine inches of fallen rain and are forecast to up to six more inches. Harry and Meghan, George Clooney, Lady Gaga and Halle Berry are among the celebrities whose mansions are under threat by the severe storms.

The National Weather Service has issued a flood watch until 4 p.m. on Tuesday covering several neighborhoods in California, and some residents have even been evacuated. During a dramatic operation in the early hours of Monday morning, LA firefighters rescued 16 people from nine properties in Studio City - the same neighborhood where George Clooney lives in his $2.2 million luxury pad. Many residents in the same neighborhood woke up Monday morning to find mud, rocks and debris strewn across the streets, while strong winds have blown bricks onto parked cars and pavements.

Harry and Meghan's $14.65million Montecito mansion is still at risk for flooding. The Duke of Sussex left his wife and two children in California to fend off the storm while he is flying back to London to visit his father following his cancer diagnosis. Meanwhile, star-studded Malibu is being marred by torrential rain, and the city is currently under a coastal flood warning, with the NWS warning residents to stay out of the water due to 'dangerous surf conditions'. The luxury beachside city is home to the likes of Halle Berry, who has a $8.5 million mansion complete with an outdoor jacuzzi that she occasionally shows off on Instagram.

Lady Gaga also owns a sprawling Malibu mansion - the same property where Bradley Cooper offered her the starring role of Ally in A Star Is Born, which she went on to win an Oscar for. But apocalyptic scenes have broken out in the beachside city, with water and mud running down the streets in some areas despite ginormous sandbags being used to prevent landslides. At least 350,000 households in the state are still without power as of Monday evening, according to national tracker poweroutage.us.

Ventura County downgraded their evacuation order to an evacuation warning, but advised there is currently no access to the area due to storm damage to the fair weather crossing. All evacuation orders for Santa Barbara County were cancelled as for 12:00 p.m. on Monday. Meanwhile in San Bernardino County, first responders rescued three people from a vehicle after it was deluged by surrounding floodwater during the night on Sunday.

Dramatic footage shows a team using lifeboat rafts to approach the vehicle before helping the occupants escape to dry land. LA firefighters have also rescued 16 people from their homes on Lockridge Road, Studio City, after a debris flow caused 'significant damage' to nine properties.

Department of Building and Safety is on scene evaluating the situation, the department said. The rain canceled the final round of the professional golf tournament at Pebble Beach in Northern California's Monterey County. Because heavy rain was forecast for Monday, the PGA Tour ended the event after only three days, naming Wyndham Clark the winner.

California Governor Gavin Newsom declared a state of emergency in eight counties with a combined population of more than 20 million people, and flash flood warnings were issued for parts of Los Angeles, Santa Barbara and San Luis Obispo counties. 'This has the potential to be a historic storm, severe winds, thunderstorms, and even brief tornadoes,' Los Angeles Mayor Karen Bass told a news conference.

Los Angeles experienced its 10th wettest day on record on Sunday - and the downtown region alone was deluged with 4.1 inches of rain. The San Francisco Bay Area and Los Angeles County were not only getting drenched but the storm was expected to stall or reverse course over some areas into Tuesday, creating severe risk of flooding and mudslides.

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