Much of California is on flood watch on Tuesday as some regions approach ten inches of total rainfall while bracing for floods and landslides.
Road blockages, landslides and toppled trees have already been reported in and around Los Angeles. A massive tree also crashed in a Los Angeles neighbourhood on Monday, damaging parked vehicles and downing power lines.
Flood watches for other regions, including the Bay Area, Sacramento and San Diego are still in effect as of Tuesday morning.
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 were blocked on Monday as rainfall intensified and floodwaters rushed onto the major roadway.
Meanwhile, Santa Barbara County officials issued evacuation warnings for some waterfront neighbourhoods, which could persist through Wednesday.
Many parts of California are already saturated from the heavy rain after a storm earlier this month caused hundreds of landslides so far.