Tsunami Awareness Week in California is prompting San Diego County to issue a warning test on Wednesday morning.
While there appears to be no threat of a quake induced giant wave, officials are making sure San Diego could be prepared should our coast ever be at risk.
Tsunamis awareness week comes with a new study by the USGS showing that more than 400,000 Californians live or work in a tsunami risk area.
Places in the tsunami zone include San Diego bay, Shelter Island, and Coronado north to Carlsbad, Oceanside and Camp Pendleton.
Dr. John Orcutt from Scripps Institution of Oceanography says there's no recorded history of a large Tsunami like in Japan hitting Southern California.
"Probably one or two hundred years. It's worth being concerned about, and thinking about and making sure people know what to do,” said Orcutt.
But San Diego could be affected by large earthquakes in the Pacific Northwest, or even a smaller one off our coast.
Two years ago, the tsunami in Japan raised water levels enough here to damage boats and docks in Mission Bay.
"In the western U.S. it could be that we'd lose substantial numbers of people because we don't have an extensive education program. But we're working on it? We're working on it. California is doing a really good job,” said Orcutt.
That work includes signs now posted in local beaches.
And Orcutt is part of a $400 million project for a global series of sensors providing even better early detection.
That Tsunami warning test will take place at 10:15 p.m. tomorrow morning. So, if you hear it on the radio or see it on television, it is just a test.