(CNN) — Tsunami waves began rolling into Hawaii early today, with readings of between 6 and 8 feet expected in some areas following the giant earthquake that struck Japan.
Communities along much of the U.S. West Coast were under tsunami warnings, too.
The first impact in Hawaii was felt shortly after 3:07 a.m. local time (8:07 a.m. ET), according to Hawaii State Civil Defense, which issued a tsunami warning.
At 3:30 a.m., television images in Honolulu showed an increase in water coming ashore.
The National Weather Service said the waves could hit Oregon and California between 7:15 a.m. and 7:30 a.m. local time (10:15-10:30 a.m. ET).
Honolulu is planning for several contingencies, because it is not certain how large the waves could be and where they may rush inland, Mayor Peter Carlisle told CNN.
“It is a very difficult situation to confront,” Carlisle said.
Hawaiian Public Radio news director Bill Dorman told CNN some roads were closed as a precaution. CNN meteorologist Rob Marciano said he expected the waves to first strike the island of Kauai.
Hawaiian emergency officials reminded residents that tsunami evacuation maps can be found in front of their telephone directories. People were being advised not to make unnecessary phone calls and a coastal evacuation was conducted.
Chief Petty Officer Kurt Fredrickson in Honolulu said the U.S. Coast Guard has been working with local port authorities and harbor masters to get the word to all mariners to get out to sea.
The Coast Guard is preparing for the worst-case scenario, Frederickson said. “We are moving our assets out to sea. We are moving our aircraft to more suitable locations.”
The threat of a tsunami prompted the U.S. National Weather Service to issue a warning for at least 50 countries or territories around the Pacific after the 8.9-magnitude earthquake struck Japan Friday. The warning for Guam was later lifted.
Warnings also were in effect for coastal areas of California and Oregon from Point Concepcion, California, to the Oregon-Washington border, according to the U.S. Pacific Tsunami Warning Center.
A warning also was in effect also for Alaska, from Amchitka Pass to Attu, and in Canada’s British Columbia.
President Barack Obama said he instructed the Federal Emergency Management Agency to be prepared to help Hawaii and other U.S. regions “that could be affected” by the disaster.
He also said the United States “stands ready to help the Japanese people” slammed by a destructive tsunami.
