The National Oceanic and Atmospheric Administration is predicting a rise in the sea level of up to 24 inches at Port San Luis around 9:07 tonight as a result of the tsunami generated by the earthquake today off America Samoa.
In a precautionary move, Cal Fire moved some 50 campers at the Oceano Dunes away from their ocean campsites, according to Ron Alsop of county emergency services.
He added that piers have been closed at Cayucos and Avila Beach.
The county coastline remains under a tsunami advisory, which also includes thecoastal areas of California and Oregon.
NOAA officials noted that people in tsunami advisory areas should move out of the water, off the beach and out of harbors and marinas.
Tsunami advisories mean that a tsunami capable of producing strong currents or waves dangerous to persons in or very near water is imminent of expected. Significant widespread inundation is not expected for areas in an advisory.
Tsunamis are a series of waves potentially dangerous several hours after initial arrival time.