A high surf advisory has been issued by the National Weather Service for the San Luis Obispo County coastline, with breakers of 10 to 14 feet possible Wednesday night and into Thursday.
The weather service said that riptides, beach erosion and minor coastal flooding are also possible.
The cause is the storm system moving down the California coast. It should arrive overnight, bringing rain and wind and a large west-northwest swell, the NWS said.
People are encouraged to stay out of the ocean and be cautious while on the beach.