A tsunami watch was issued for coastal areas from Washington to California early Tuesday after a magnitude 7.9. earthquake struck the Gulf of Alaska — but there were no early reports of any waves.
A full tsunami warning was also in effect for the coasts of Alaska and the Canadian province of British Columbia. A tsunami watch was also issued for Hawaii but was later canceled.
The quake struck at 12:31 a.m. local time (4:31 a.m. ET) about 181 miles southeast of Kodiak, Alaska, at a depth of about 6.5 miles, the Alaska Earthquake Center said. The quake’s strength was later revised downward from an initial reading of 8.2 magnitude. A number of smaller aftershocks were recorded nearby, according to the United States Geological Survey.
The earliest wave was predicted to have reached Kodiak at 1:45 a.m. local time (5:45 a.m. ET), and warning sirens sounded over the town of more than 6,100 people.
Kodiak police said just before 2:30 a.m. local time (6:30 a.m. ET) that officers reported water was receding from the harbor and residents should remain in place and await further updates.As a precaution, state police in Kodiak said residents on lower ground were being urged to move to higher ground because the tsunami warning was still in effect. A local high school was opened as a shelter.
Waves were forecast to reach the Washington coasts at or after 4:50 a.m. local time (7:50 a.m. ET), the USGS said, and California from 5:20 a.m. local time (8:20 a.m. ET).
The NWS Tsunami Warning Center advised that “widespread hazardous tsunami waves are possible.”
The San Francisco Department of Emergency Management tweeted that people within three blocks of the Pacific Coast or five blocks of the San Francisco Bay should be prepared to evacuate.
A buoy located 188 nautical miles southeast of Cordova, Alaska, recorded a wave of about 30 feet, according to NOAA data, although it was unclear if this was related to the quake.
“We know one of the buoys showed a significant water rise right next to where the earthquake happened but the next buoy didn’t seem to experience that,” NBC News meteorologist Bill Karins said. “We don’t know yet what this means. It could have malfunctioned. We just don’t know at this stage. It’s too early to tell.”
He added: “If anyone is still on the coast, the message is still get out of the way until we know more.”