The affected area stretches from St. Joseph to Manistee.
The weather bureau says beaches with particularly dangerous conditions include Grand Haven State Park, Pere Marquette in Muskegon and South Beach in South Haven. The south sides of piers will be especially risky for swimmers.
The statement calls for:
* High wave action, with strong currents and dangerous swimming conditions expected.
* Strong structural currents expected.
* Strong longshore currents expected.
* Rip currents possible.
* Gusty southwest winds and waves of 3-5 feet are expected. Winds and waves will diminish this evening.
High wave action makes swimming difficult and can tire even a strong swimmer quickly.
Structural currents form along piers where longshore currents and wave action flow into the structure. Structural currents can sweep you out into deeper water along the pier structure.
A longshore current is a lake current that moves parallel to shore. Longshore currents can be strong enough to prevent swimmers from being able to keep their feet on the bottom, making it difficult to return to shore.
Rip currents are powerful channels of water flowing quickly away from shore, which occur most often at low spots or breaks in sandbars. Rip currents can sweep you into deeper water.
The forecast for the Grand Haven area:
• Tonight: Mostly cloudy, with a low around 59. West-southwest wind 11 to 16 mph.
Wednesday: A 30 percent chance of showers. Mostly cloudy, with a high near 64. West-northwest wind 11 to 13 mph.