Update: Tsunami warning canceled for portions of US West Coast following magnitude-7 quake

Update at 10:09 a.m. Dec. 5: The National Tsunami Warning Center in Palmer, Alaska, canceled the tsunami warning that was in effect for areas along the California and Oregon coasts, including San Francisco, following a magnitude-7 earthquake earlier today about 40 miles north-northwest off the coast of northern California.

No destructive tsunami has been recorded and no tsunami danger exists for the U.S. West Coast, British Columbia in Canada or Alaska.

Original post at 9:39 a.m. Dec. 5 (updated at 9:55 a.m.): An extremely shallow magnitude-7 earthquake struck at 8:44 a.m. Hawai’i time about 39 miles west-northwest of Petrolia, Calif., at a depth of less than a half-mile under the waters of the Pacific, triggering a tsunami warning for communities along portions of the California and Oregon coasts.

But while a tsunami threat looms over parts of the U.S. West Coast closer to the earthquake’s center, the Pacific Tsunami Warning Center in Honolulu says based on all available data, there is no threat of tsunami waves in Hawai‘i from the quake.

“Repeat. Based on all available data, there is no tsunami threat to Hawai’i,” said the center in an information statement issued just before 9 a.m. Thursday.

The tsunami warning is in effect for the California coast from Davenport, 10 miles northwest of Santa Cruz, to the Oregon-California border and includes San Fancisco Bay.

It also includes the Oregon coast from the state’s border with California to the Douglas County-Lane County line, 10 miles southwest of Florence, Ore.

The level of tsunami danger is being evaluated for other U.S. and Canadian Pacific coast areas. More information will be provided in supplementary messages.

The National Tsunami Warning Center in Palmer, Alaska, had no tsunami observations available to report as of 9:54 a.m. Hawai’i time; however, tsunami activity was forecast to have started in several places already, including Fort Bragg and Crescent City in California and Port Orford, Brookings and Charleson in Oregon.

Tsunami activity is forecast to begin in the next 10 to 15 minutes or so in the San Francisco area.

Impacts will vary at different locations in the warning areas.