A storm of historic proportions swept through Hollywood Hills in L.A., causing debris and leaving 1.1 million people without power.

On Monday, Los Angeles experienced a historic storm that caused record rainfall, posing dangers for the city's homeless population and knocking out power for over a million people in California.

Over the past few days, the state has experienced its second storm fueled by an atmospheric river. In the Los Angeles area, including Hollywood Hills and Beverly Hills, about 1.4 million people were under a flash flood warning on Monday morning. Up to 9 inches (23 centimeters) of rain had already fallen in the area, with more expected, according to the National Weather Service. The flash flooding and mudslide threat in this region is particularly dangerous.

Rescue crews were already working in Southern California to save individuals from fast-moving water.

In Studio City, a neighborhood known for its multimillion-dollar homes, gushing rivers carried mud, rocks, and objects such as coolers, ladders, and plastic crates, causing damage to several homes, including one with a crumpled garage door from the debris slide.

On Sunday, Keki Mingus received a late alert about a neighbor's house atop a hill experiencing difficulties.

Water, mud, and rocks surged through two houses and into our street, as Mingus exclaimed at dawn on Monday. 'I can't believe it,' he said, 'It looks like a river that's been here for years. I've never seen anything like it.'

On Sunday, downtown Los Angeles experienced a new rainfall record of 4.1 inches (10.41 centimeters), surpassing the previous record of 2.55 inches (6.48 centimeters) set in 1927, as reported by the National Weather Service.

Despite the unexpected interruption, the Grammy Awards proceeded as scheduled at Crypto.com Arena on Sunday night.

Up to 8 inches (20 centimeters) of rainfall is expected in Southern California's coastal and valley areas, with 14 inches (35 centimeters) possible in the foothills and mountains over the next two days, according to the weather service forecast.

On Monday morning, over 474,061 homes, businesses, or other locations were without electricity across the state, according to poweroutage.us. Meanwhile, commuters had to navigate through several inches of floodwater to reach Union Station in downtown Los Angeles to catch their trains.

The devastation in Southern California on Monday was caused by the heavy rainfall and strong winds over the weekend in the San Francisco Bay Area, which resulted in flooded streets, fallen trees, and damaged power lines. Wind speeds of over 60 mph (96 kph) were recorded in some areas, with gusts reaching up to 80 mph (128 kph) in the mountains.

In San Jose, emergency crews rescued people from a homeless encampment and pulled occupants out of a car stranded by flooding.

In Yuba City, approximately 100 miles (160 kilometers) from San Francisco, police are investigating the death of a man discovered under a large redwood tree in his backyard on Sunday evening. According to Facebook, a neighbor heard the tree fall and it is believed that the man may have been using a ladder to attempt to clear the redwood when he tragically met his end.

A hurricane force wind warning was issued by the weather service for the Central Coast, with wind gusts of up to 92 mph (148 kph) possible from the Monterey Peninsula to the northern section of San Luis Obispo County.

Officials in Southern California issued warnings of potentially devastating flooding and ordered evacuations for canyons that burned in recent wildfires and are at high risk for mud and debris flows.

On Sunday, 19 individuals were saved in Long Beach following the loss of their 40-foot sailboat's mast, as stated by Brian Fisk, a firefighter and paramedic for the Long Beach Fire Department.

On the marine radio, a vessel picked up a distress call and assisted in rescuing eight individuals. Meanwhile, 11 people managed to reach the rocky breakwater near Alamitos Bay, where they were saved by lifeguards. One person received medical attention for injuries.

Fisk remarked, "They were fortunate to go sailing amidst strong winds and turbulent weather."

The Governor's Office of Emergency Services activated its operations center and positioned personnel and equipment in areas most at risk in response to Gov. Gavin Newsom declaring a state of emergency for Los Angeles, Orange, Riverside, San Bernardino, San Diego, San Luis Obispo, Santa Barbara, and Ventura counties.

Emergency shelters were set up in various regions, including Santa Barbara and Los Angeles Counties, as evacuation orders were issued.

Topanga Elementary Charter School and Vinedale College Preparatory Academy are the only schools in the Los Angeles Unified School District that will not be open on Monday.

Numerous streets in Santa Barbara County were flooded Sunday, leading to the cancellation of classes for schools in the area. The region, which was devastated by deadly mudslides in 2018, is still recovering from the disaster.

Palisades Tahoe, a ski resort located 200 miles northeast of San Francisco, announced on Sunday that it was expecting the heaviest snowfall of the season, with an accumulation of 6 inches per hour for a total of up to two feet. The heavy snow was expected to continue into Monday throughout the Sierra Nevada, and motorists were advised to avoid mountain roads.

The state had been drying out after the atmospheric river-powered storm that hit last week. These rivers are narrow plumes of moisture that form over an ocean and can produce heavy rainfall when they move over land.

The "Pineapple Express" refers to both atmospheric rivers because their moisture plume extends back to Hawaii.

Todd Hall, a meteorologist with the National Weather Service near Los Angeles, stated that we've experienced flooding and gusty winds, adding that we've had the full range of weather conditions.