A powerful earthquake that struck off the coast of Russia has generated tsunami warnings and advisories for a broad section of the Pacific, including Alaska, Hawaii and the U.S. West Coast

The U.S. Tsunami Warning System ( tsunami.gov) will be updating its guidance as experts learn more about the threat, including maps showing what areas face what risks. In the minutes and hours after a major earthquake, tsunami assessments change as researchers track data from buoy and other interments.