A rip current is a narrow jetlike stream of water that flows sporadically seaward for several minutes. Such currents are probably the cause of most ocean bathing accidents blamed on undertow. The term riptide is often used but is a misnomer, the currents being related in no way to tides.

Swimmers caught in a rip current should not attempt to swim shoreward directly against the current. Instead, it is best to swim a short distance parallel to the beach to emerge from the rip current before returning to shore.

A rip current is strongest and fastest nearest the surface of the water.

Contrary to popular belief, a rip or undertow cannot pull a person down and hold him under the water. A rip simply carries floating objects, including people, out to just beyond the zone of the breaking waves, at which point the current dissipates, and releases everything it is carrying.

Rip currents form at long coasts that are approached by wave trains oriented parallel or nearly parallel to the shoreline.

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