Riptides at the Shore Kill 3

Treacherous rip currents killed at least three swimmers at the Jersey Shore over the weekend, one in Atlantic City and two others in Wildwood. As Hurricane Bertha weakened to a tropical storm, so did the effect she is having on the shore, where waves and swells looked calmer than they had in days. A mostly cloudy sky today might have kept many away from the beaches, where the surf still kicked up. But moderate to high waves are expected over the next few days, according to the National Weather Service.

Rip currents are strong, rushing channels of water that flow along the shoreline and pull seaward, taking swimmers with them. They are stronger when the tide is low and the surf is rough, as when a hurricane is brewing off shore, or when strong onshore winds blow. Rip currents sometimes prove deadly when inexperienced or weak swimmers get caught in them and panic as they are being pulled away from the shoreline. The tide can move a person or object up to 8 feet per second which is faster than an olympic swimmer.

In Wildwood, three men went swimming around 7 p.m. Saturday, after lifeguards were off duty for the day. The swimmers were caught in a rip current that claimed the life of one of them. A second swimmer is still missing and presumed drowned, while a third was hospitalized.

Strong currents, driven by Bertha, threatened the safety of swimmers along the Jersey Shore all weekend, forcing beach patrols to make hundreds of rescues. In Atlantic City alone, 57 rescues were conducted between Saturday and Sunday.

Rip currents create the need for more than 18,000 lifeguard rescues a year in the U.S. and cause about 100 deaths - more than all other natural hazards except heat and floods - according to the National Weather Service.