The deadly storm caused widespread damage across northern California, bringing record rainfall and snowfall along the coast.
Huge waves washed away the walls of houses, and mudslides, sinkholes and flooding were reported across the region.
Two deaths were reported on Thursday. A toddler died after a tree fell on his house, and a 19-year-old woman died when she crashed her car due to the wet road.
The weather forecast for the weekend and next week promises to be more ominous.
As of Friday morning, more than 97,000 homes and businesses were without power after hurricane-force winds toppled large trees and downed power cables.
The San Francisco area is still recovering from the flooding and forecasters say rainy and windy weather is on its way.
The rain fell on areas that were already soaked from the New Year’s Eve storm.
A resident of the coastal community of Cambria in San Luis Obispo County was hit by an “unusually large rogue wave” at his home Thursday morning.
“The waterfront-facing houses’ windows were smashed and a resident was knocked over by the massive wave,” said the Cambria Fire Department, adding that “the water damage has extended to the entire house.”
Homes were also damaged in Monterey and Humboldt counties, where officials in the city of Shelter Cove warned that the waves “could easily wash people and pets into the ocean.”
Parts of the Capitola Pier in Santa Cruz County collapsed under 35 feet (10.6 meters) waves.
Tony Valdez, who has lived in Santa Cruz for 28 years, said seeing the damage to the pier left him in “disbelief”.
“I mean, it must have taken a huge hit for that damage,” he told CBS News, the BBC’s US partner. “That’s why you have to have a lot of respect for the ocean and the water.”
Capitola restaurant owner Joshua Kochanek said waves hit his business roughly every 10 minutes.
“The waves were coming and all the damage. It was knotty. It kept you on your feet,” he said.
Shelters have been opened for residents who have been told to evacuate their homes due to fears of flooding and landslides on hillsides that have been damaged by recent forest fires.
Beaches along the coast were also ordered to close.
Further inland, the Sierra Nevada mountains have accumulated more than 1 foot of heavy snow and more are expected.
Up to three extra feet of snow are expected in the mountains in the coming days, according to the National Weather Service.
A “stronger” atmospheric river is expected to arrive on Monday and continue into Tuesday, bringing more rainfall and gusty winds.