Almost the entire state of California is on flood watch on Monday as some regions approach ten inches of total rainfall and brace for possible tornadoes.
Santa Barbara County officials have issued evacuation warnings for waterfront neighbourhoods as a destructive storm hits the region. The warning could persist through Wednesday.
Meanwhile, more than 37 million people in the state are facing strong winds, torrential rain and heavy mountain snow until Wednesday, according to the National Weather Service (NWS).
Tornadoes are also possible in the Sacramento Valley region, according to forecasters, along with the slight risk of severe thunderstorms over parts of inland northern California. Supercells, which can cause tornadoes and hail, have started to form over central California.
Officials are warning Californians to avoid road travel and prepare for power outages, mud or rock slides and coastal flooding. Portions of the US-101 and Pacific Coast Highway are already blocked as rainfall intensifies and floodwaters rush onto the major roadway.
Meanwhile, some of California’s most iconic cities, like Calabasas and Malibu, are under flash flood warnings until this evening.
Many parts of California are already saturated from the heavy rain and there have been hundreds of landslides so far.
Record rainfall, triple-digit winds, hundreds of mudslides. Here's California's storm by the numbers