Quake But No Tsunami Along California Coast Californians got a tsunami warning last night, after a magnitude 7 earthquake struck off its northern coast. Emergency workers as far south as San Diego, including lifeguards on the night shift, headed for the water to warn of possible danger. It was no joke in the northern town of Crescent City, California. A tsunami there in 1964 carried away 29 city blocks, and left eleven people dead. This time, no wave appeared.