During a demonstration Wednesday, a lifeguard acting as a swimmer in distress was pulled by the current while treading water.
The whistle was blown, the lifeguard signaled for her to come in, and when she did not, and a lifeguard swam to her and brought her to safety.
Officials said a riptide is a strong, fast-moving current that flows away from shore and can pull swimmers farther into the ocean.
They advised beachgoers to watch for signs such as different-colored water or a break in the wave pattern.
Lifeguards also emphasized the importance of remaining calm if caught in a rip current.
"I would say a lot of people do try and fight it and then they get over-exhausted and that is the worst thing you can do for yourself, luckily, we are watching," said lifeguard Noelle Russo.
Officials said swimmers should swim parallel to the shore to escape a riptide.
The warning comes after three people were rescued from a riptide at Robert Moses on Tuesday night.
According to officials, three off-duty lifeguards who were surfing nearby brought the swimmers to shore.
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