(CBS/AP)---Tsunami waves spawned by a massive earthquake in Japan have hit Hawaii.
The Hawaii-based Pacific Tsunami Warning Center (PTWC) said Kauai was the first island hit early Friday by the tsunami, which was quickly sweeping through the Hawaiian Island chain.
Waves about 6 feet high were recorded on Maui, and 3 feet in Oahu and Kauai. Officials warned that the waves would continue and could become larger, but a scientist at the tsunami warning center said it didn't appear that they would cause major damage in the state.
"But there is going to be some damage, I'm sure," said geophysicist Gerard Fryer in Hawaii.
Tsunami warnings stretch along the entire western coast of the United States and Canada, from the Mexican border to Chignik Bay in Alaska.
Waves are expected on the mainland between 7 a.m. and 8 a.m. Pacific time.
Webcams showed a long series of waves slowly reaching up to break walls along Honolulu's Waikiki Beach, whose topography protects it from the greatest impact. Then, the water dramatically receded, exposing reefs near Diamond Head.
"It's rather disturbing," Dr. Dan Walker, tsunami adviser to the Oahu Civil Defense Agency, told KGMB. "Historically in Pacific tsunamis, the first wave is not the largest."
"It doesn't paint a very good picture; anybody who thinks because the first wave is relatively small and takes comfort in that may be making a mistake," Dr. Walker said.
At Pearl Harbor half-meter wave heights were reported "without incident," according to CBS affiliate KGMB. No damage to piers was reported.
Residents in coastal areas of Hawaii were evacuated to refuge areas at community centers and schools while tourists in Waikiki were moved to higher floors of their high-rise hotels.
Roadways and beaches were empty as the tsunamis struck the state, which had hours to prepare. All harbors are closed and vessels were being ordered to leave the harbor.
The entire U.S. Pacific Coast is bracing for a tsunami following the devastating 8.9-magnitude that struck Japan.
The tsunami warning was widened beyond East Asia early Friday to include Hawaii, Australia, New Zealand, the entire U.S. western coast, Mexico and Central and South America and the rest of the Pacific Ocean.
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