Snider, however, urged people to not ignore such warnings — which remain quite rare — or head to the beach to watch the waves. “Refresh what it means to live in tsunami country," Snider said.

Hear powerful survivor stories from the 2004 Boxing Day tsunami. It’s been 20 years since one of history’s deadliest natural disasters. Discover how tragedy defined a generation.

The tsunami killed an estimated 130,000 people in Aceh. The densely populated Banda Aceh was the worst-hit — with some 60,000 people dead and many more missing.