Glossary
Longshore current
A current that runs parallel to the beach, created when waves hit the shore at an angle. It can carry swimmers along the shore.
A longshore current is a current that flows parallel to the beach, inside the surf zone. The National Weather Service in Brownsville, Texas (opens in a new tab) explains that longshore currents form when waves approach the shore at an angle, and that they run in the same direction as the breaking waves. They are strongest in the middle of the surf zone, and larger waves make them faster.
Why they matter:
- a longshore current can carry a swimmer or a small child down the beach, away from where their family and the lifeguard are watching;
- the NWS says longshore currents are always present alongside rip currents as part of the same circulation, and they can feed and strengthen a rip near jetties or other structures;
- deeper water between sandbars can make them more dangerous.
In practice, this is another reason to stay within arm's reach of young children in the waves, to keep checking your position against a landmark on shore, and to swim near a lifeguard. Rip currents pull you out; longshore currents pull you sideways. See rip currents and shore break, big waves and sandbars.
What you can do today: before you get in the water, pick a landmark on shore so you can tell if you are drifting.