FOX Weather Meteorologist Ian Oliver explains how an earthquake can cause a tsunami.

HONOLULU – Parts of Alaska are under Tsunami Warnings while the entire U.S. West Coast and the state of Hawaii are under Tsunami Watches after a monster magnitude 8.7 earthquake struck off the east coast of Russia Tuesday evening.

The quake hit at 1:24 p.m. Hawaiian Time (7:24 p.m. ET, 2:24 a.m. Wednesday local time) about 85 miles east of Kamchatsky off the eastern Russian coast.

Russia Earthquake

(FOX Weather)

The Pacific Tsunami Warning Center says a quake of that magnitude may have triggered a tsunami that would be destructive to coastal areas even far from the epicenter.

Initial data from the quake suggest tsunami waves reaching more than 9 feet above the tide level are possible along some coasts of the Northwestern Hawaiian Islands and Russia, according to the PTWC. Waves of 3-9 feet (1-3 meters) are possible along some coasts of Hawaii, Japan, and Guam.  The first waves would reach Hawaii around 7 p.m. Hawaiian Time (1 a.m. ET).

West Coast Tsunami Alerts

(FOX Weather)

The threat to the U.S. West Coast is still under evaluation. But the PWTC says any first waves wouldn’t reach the Washington and Oregon coasts until 11:40 p.m. PT (2:40 a.m. ET), around San Francisco around 12:40 a.m. PT Wednesday, and aroun the Los Angeles coast around 1:05 a.m. PT.  

Hawaii Tsunami Alerts

(FOX Weather)

Waves are expected to reach Shemya at 4:46 p.m. Alaska Daylight time, and 5:46 p.m. AKDT in Adak.

“For other US and Canadian Pacific coasts in North America, the level of tsunami danger is being evaluated,” the PTWC said. “Further information will be provided in supplementary messages.

Updates to follow soon.