Record rainfall was reported in downtown Los Angeles, with 2.86 inches breaking the record for the day of 2.71 inches set in 1954.
According to the National Weather Service, rainfall rates were recorded in some areas at levels as three-quarters of an inch to 1.2 inches per hour -- well above the rate that can typically trigger flooding or debris flows.
LAFD member escapes truck swept into the ocean by mudslide during heavy downpours in Malibu
In the Hollywood Hills, the Los Angeles Fire Department reported a debris flow that parked 8 inches of mud on Mulholland Drive. No injuries were reported, but crews scrambled to ensure the safety of structures above and below the slide area.
The rain caused a rockslide and pushed mud onto the road in Malibu Canyon, and a large debris flow left about 8 inches of mud across a road in the Hollywood Hills.
The Weather Service has described the multi-day storm system as likely to be "the biggest precipitation producer so far this season.''
By the time the storm moved out of the region, 1.4 to 3.5 inches of rain fell in most coastal and valley areas; 3.4 to 6.6 inches drenched the foothills and mountains.
Despite recent storms, much of Southern California remains in extreme or severe drought, according to the U.S. Drought Monitor. Daniel Swain, a climate scientist at the University of California, Los Angeles, said that while the area is desperate for rain, this storm might bring too much too quickly.