The National Oceanic and Atmospheric Administration's West Coast/Alaska Tsunami Warning Center says it happened during the afternoon of June 13 in close conjunction with a weather system known as a low-end derecho. The tsunami was detected by more than 30 tide gauges.
Brian Coen told observers he was spear fishing near the mouth of Barnegat Inlet when he spotted a strong outgoing tide expose rocks before he saw a wave 6-feet high span the inlet.
Two of three people who were swept off the rocks of the jetty by the wave required medical attention.
Scientists say it's also possible the slumping at the Continental Shelf east of New Jersey played a role.