Great Lakes, great danger (rip currents)

The Grand Rapids Press carries this article on the dangers of rip currents on the lakes:

This year, the National Weather Service will begin posting rip current alerts for the Great Lakes on its Web page, www.crh.noaa.gov/grr/. Parks on the shoreline will factor the forecasts into their usual warning flags: green for safe, yellow for caution, red for unsafe. The National Weather Service, the United States Lifesaving Association and the National Sea Grant Program are collaborating to educate the public.

Rip currents -- not to be confused with an undertow -- occur when wind pushes water onto a beach and a sand bar forms close to shore. If the sand bar breaks, the water rushes back out in a narrow channel. These mini-rivers can be as wide as 100 feet, and can move faster than five miles an hour, too fast for even an expert swimmer to combat.

Rip currents aren't easily predicted, which is why we all need to educate ourselves and take precautions. High surf or a nearby pier or jetty can create rip tide conditions. Michigan Sea Grant, a joint educational effort of Michigan State University and the University of Michigan, warns people to watch out for: a break in wave patterns; a clear channel of churning, choppy water; a line of foam or debris moving seaward; or a difference in water color.