Beachgoers are being urged to stay vigilant due to rough surf conditions and several shark sightings.

Lifeguards on the South Shore have recently reported rip current conditions due to Isaias.

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At Jones Beach, swimmers were hit by large waves and lifeguards said that was during moderate rip conditions.

A full moon and a potential storm could bring rough waters ahead for Long Island beaches, according, to park officials.

"Not only are we going to have dangerous swimming condition—we're also concerned about erosion," says New York State Parks Regional Director George Gorman. "Full moons usually bring the highest tides and that's going to be combined with the storm tide."

About a dozen sharks were also spotted at Nassau County beaches recently. A sighting of a shark came at around 1:15 p.m. Saturday when a fin was spotted at Lido Beach and everyone was forced out of the water.

Officials are telling residents to stay close to shore, swim in groups and listen to the lifeguards.