The potent storm system could mean more danger in the area in the coming days, geologist Pat Abbott told CNN affiliate KCBS-TV.
"Sea levels are rising, gravity is pulling, and now when you talk about heavy rains coming in this week, might that be a danger? Oh definitely. That's going to add to the problem," Abbott said.
Abbott told the station a big landslide is typically followed by "a lot more landslides." His advice to locals: "Back off."
KCBS-TV footage showed part of the hillside crumbling onto the beach, unleashing a massive dust cloud as rocks and debris pushed a pickup truck across the sand. The pickup was unoccupied. At least one home was evacuated, the station reported.
City officials and geologists were reviewing "soil, rock, and groundwater conditions to evaluate the safety of the area and nearby structures," according to the statement.
Most coastal communities will pick up 1 to 3 inches of rain through the weekend, and some areas of northern and central California could receive 3 to 5 inches of rain in total. Coastal erosion and flooded roadways are a major concern.