Tsunamis Seen Possible Along U.S. East Coast. Newly-discovered sea floor cracks off the mid-Atlantic coast, if geologically active, could trigger tsunamis along this heavily-populated coast. Geologists predict that the “tidal waves” would be on a par with the storm surges caused by class-three or -four hurricanes. 1992’s Hurricane Andrew, a class-four storm, was the costliest natural disaster in human history, largely because of its storm surge damage.