 At 3 @,@ 720 kilometers ( 2 @,@ 310 mi ) distant , the tsunami was perceptible on the Hawaiian island of Maui at Kahului . The location of the islands lay on a great circle route that is also perpendicular to the region of ( presumed ) uplifted land at the coast near Cape Mendocino and any energy distributed would be the strongest in that direction . No tsunami was detected at Johnston Atoll , 5 @,@ 050 kilometers ( 3 @,@ 140 mi ) from Cape Mendocino in the north Pacific Ocean , but bottom pressure recorders registered a maximum amplitude of .4 cm ( 0 @.@ 16 in ) in 4 @,@ 000 meters ( 13 @,@ 000 ft ) of water in the Gulf of Alaska , with 3 @.@ 75 hours of travel time . While the waves generated by the earthquake were limited , the event demonstrated the rapid onset of tsunami hazards , giving little time for coastal residents to prepare . And in this case , the strongest waves came ashore in Crescent City three to four hours after the initial surge , but it is possible to be just the opposite where the first waves could be the strongest . Also detailed from this event was that the wave hazard can be of long duration , with wave action lingering for more than eight hours . 
