The last destructive teletsunami occurred in 1964 following the great Alaska earthquake. As the Hawaii Regional Tsunami Warning Center , PTWC provides a more rapid warning for local tsunamis generated in Hawaiian waters. Two significant local tsunamis have been generated in Hawaii in historical times, one in 1868 and one in 1975. Both were caused by major earthquakes that displaced the sea bottom along the southeast flank of the island of Hawaii. Although these tsunamis caused damage and casualties only on that island, a future local tsunami could have adverse effects further up the island chain.
Local tsunamis strike nearby shores almost immediately after being generated by the earthquake.
Consequently, the earliest warning for a local tsunami is the strong shaking of the ground, and persons near the shoreline that feel strong shaking should evacuate immediately without waiting for an official warning.