The 1946 Aleutian Tsunami: Hawaii's Most Devastating Tsunami on Record

April 1, 1946

A magnitude 8.6 earthquake struck the Aleutian Islands (Alaska) at 1:00 AM AST. The resulting tsunami raced across the Pacific at 500+ mph.

Impact on Hawaii

• Arrival: ~4.5 hours later.
• Wave heights: Up to 30 ft (9 m) in Hilo.
• Deaths: 162 in Hilo alone; 1,500+ Pacific-wide.
• Damage: Downtown Hilo waterfront destroyed; waves wrapped around islands hitting all coasts.

Elsewhere

Chile: flooding in Valparaíso. Japan: minor damage in Hokkaido/Honshu.

Legacy

Prompted creation of the Pacific Tsunami Warning Center (1949) in Honolulu. April 1 is now Tsunami Awareness Day in Hawaii.

No subsequent tsunami has matched its destruction in Hawaii.