A group of waves traveling across the ocean from a distant storm is called a swell.
Swell forms when wind transfers energy to the ocean, often across a large area known as the fetch. Once the waves move away from the storm, they can travel long distances and become more organized than the locally generated wind waves near shore. Surfers track swell direction, period, and height to predict conditions.
Wave period is the time between successive wave crests. A longer-period swell generally carries more energy and can produce stronger, more powerful waves when it reaches a suitable coastline. The resulting surf still depends on local bathymetry, tide, wind, and the angle at which the swell approaches land.
Swell is not the same as a rip current, which is a narrow flow of water moving away from shore. Whitewater is broken-wave foam, while backwash is water flowing back toward the sea after reaching the beach.