The earthquake initially registered a magnitude 7.7 from the United States Geological Service, but that was later downgraded to 7.5, and its epicenter was placed at 63 miles west of Craig.
A tsunami warning is in effect for portions of British Columbia, Canada, and southern Alaska, officials said.
The West Coast and Alaska Tsunami Warning Center said that a “tsunami with significant widespread inundation is expected.” The tsunami warning included areas southeast of Cordova, Alaska, and ran to the north tip of Vancouver Island.
There were no initial reports of damage from the quake.
The Juneau Empire, an Alaskan newspaper, quoted one resident of that city, Archie Hinman, as saying the quake “shook my Juneau home violently enough to awaken the entire family.” But he added that there was no apparent damage to the home.
The quake struck at about 3:58 a.m. ET off the coast of Alaska.
Based on available data, the tsunami warning center said there is “no destructive threat” to Hawaii, though it warned that some coastal areas could experience larger waves and strong currents.