A tsunami warning was in effect for Hawaii Saturday following a massive earthquake that struck central Chile.
The Pacific Tsunami Warning Center also issued a tsunami advisory for the coast of California and an Alaskan coastal area from Kodiak to Attu islands.
The first waves were expected to arrive in Hawaii at 11:19 a.m. Saturday (4:19 p.m. EST).
The center said a tsunami has been generated that could cause damage along coastlines of all islands in the Hawaii. It said a tsunami in California and Alaska was possible.
The Ewa Beach, Hawaii-based center called for "urgent action to protect lives and property" in Hawaii, which is among 53 nations and territories subject to tsunami warnings.
"The main thing is we want everyone to take this event seriously," said Charles McCreery, director of the center.
McCreery said he didn't know how big the waves will be, but he expected them to be the largest to hit Hawaii since 1964.
If coastal areas are evacuated, visitors in Waikiki would be moved to higher floors in their hotels, rather than moved out of the tourist district, which could cause gridlock.
"We've got a lot of things going for us," McCreery said. "We have a reasonable lead time. The evacuation should all take place during daylight hours, and wave impact should be during daylight hours.
"We should be able to alert everyone in harm's way to move out of the evacuation zones."
Barry Hirschon, also of the Tsunami center, said the advisory for the California coast and parts of Alaska was the agency's lowest level alert.
"It's a heads up that there's been a tsunami event and it could affect the coasts later," Hirschon told CNN. "I don't think it will be updated to a warning."
The largest earthquake ever recorded struck the same area of Chile in 1960. The deadly wave that it caused raced across the Pacific and hit the Hilo area of the Big Island, where 61 people were killed.