While there is a possibility of hurricane activity in Southern California, the possibility of Florence making landfall there is nonexistent. History shows that hurricane landfall is possible, but if it happened, it would be in Southern California. Southern California is the only part of the Pacific Coastline in the lower forty-eight that could see a tropical storm or hurricane landfall from the Eastern Pacific.
The hurricane would have to be fast enough over the cold Pacific Ocean to maintain intensity all the way to the coast. The primary threat from California tropical cyclones isn't winds or storm surge. It's rainfall, which is sometimes torrential, which leads to flooding, damage and occasionally casualties. Usually, only the remnants of tropical cyclones affect California.