The tsunami was expected to hit the Washington coast starting at about 7 a.m. with the largest wave — about 3.3 feet — expected at Moclips in Grays Harbor County, said Rob Harper, a state Emergency Management spokesman.
Waves were expected to be smaller around the larger coastal cities of Aberdeen and Hoquiam.
Residents around Moclips, Pacific Beach, Iron Springs and Taholah who live close to the ocean were asked to move to higher ground, the Grays Harbor Emergency Management agency said.
Harper says the Quinault Indians were looking at limited evacuations in the Taholah area. Farther north, members of the Makah and Hoh Indian tribes were coordinating their public safety efforts with Jefferson County.
In southwest Washington's Pacific County, Sheriff Scott Johnson said the county activated its reverse 911 system, phoning residents on the coast and in lowlying areas and asking them to move to higher ground.
An order evacuation was under way before dawn in Long Beach, Ilwaco and Ocean Park, Johnson said.
"We certainly don't want to cry wolf," he said. "We just have to hope we're doing the right thing based on our information. We don't want to be wrong and have people hurt or killed.
"In the last 25-30 years, this is the second time I've been involved in an evacuation for this reason," the sheriff added.
Buses stand ready to pick up nursing home residents from lowlying Pacific County areas if need be, Johnson said.
Harper warned that people need to stay off the coastal beaches for 12 hours since the tsunami will arrive in a succession of waves.
The size of the wave could also be amplified by the tide — low this morning but higher as the day goes on, Harper said.