Thailand 2004 Tsunami, One of th. Deadliest Natural Disasters On December 26, 2004, a catastrophic tsunami struck Thailand, triggered by a massive 9.1-9.3 magnitude earthquake off the coast of Sumatra, Indonesia. The undersea quake unleashed powerful waves that slammed into Thailand's western coastline, devastating areas like Phuket and Khao Lak. Entire coastal communities were swept away, and thousands of lives were tragically lost. Thailand was among the hardest-hit countries in a disaster tha