Rip Tides
a danger to swimmers

Another almost overlooked aspect of hurricanes and tropical storms are rip tides (or rip currents). Rip tides are strong sea currents which push away from the shore as a strong storm is near. They are formed by the strong winds pushing water towards the shore. Tropical cyclones' winds push waves up against the shoreline even if they are hundreds of miles away, so rip tide warnings are often the first indication of a nearby hurricane.

As seen in the side view diagram below, the incoming waves create an underwater sandbar close to shore, and the waves push more and more water in between the sandbar and the shore until a section of this sandbar collapses.

All the excess water is forced through this gap, creating an extremely strong but narrow current away from the shore (seen in top view diagram above). In fact, rip tides are so strong that trying to swim back to shore against the rip tide current will only tire you out and make it that much more difficult for you to survive. Rip tides are narrow enough that if you swim parallel to shore, you can easily escape the current and then swim back to shore.

Terms for using data resources. CD-ROM available.
Credits and Acknowledgments for WW2010.
Department of Atmospheric Sciences (DAS) at
the University of Illinois at Urbana-Champaign.