Waves of up to two metres high are already being seen in Hawaii in the wake of the massive earthquake in Japan -- and officials warn they could become larger.
Kauai was the first of the Hawaiian islands hit by the tsunami, with water rushing ashore in Honolulu and swamping the beach in Waikiki.
But the waves have stopped short of the area's high-rise hotels.
Evacuations have also been ordered along the U-S west coast and a tsunami watch has been issued for sections of the B-C coast, including parts of Vancouver Island.
Emergency officials are warning people to get off beaches and not to go there to watch for any big waves, as has happened with some previous tsunami watches