A rip current, often simply called a rip, is a specific kind of water current which can occur near beaches with breaking waves, such as an outflow gap between sandbars. A rip is a strong, localized, and narrow current of water which moves directly away from the shore, cutting through the lines of breaking waves like a river running out to sea, and is strongest near the surface of the water. A rip current forms because wind and breaking waves push surface water towards the land, and this causes a slight rise in the water level along the shore. This excess water will tend to flow back to the open water via the route of least resistance. When there is a local area which is slightly deeper or a break in an offshore sandbar or reef, this can allow water to flow offshore more easily, and this will initiate a rip current through that gap.