At 621 PM EDT, Doppler radar was tracking a strong thunderstorm near Brooklyn, or 9 miles southeast of Jackson, moving northeast at 30 mph. HAZARD. Winds in excess of 40 mph. SOURCE. Radar indicated. IMPACT. Gusty winds could knock down tree limbs and blow around unsecured objects. Locations impacted include. Brooklyn. Grass Lake. Vandercook Lake. Leoni. Napoleon. Norvell. Clark Lake. Lake Columbia. Oak Point. Sunset Beach. Michigan Center. Munith.

* WHAT. High wave action, strong currents, and dangerous swimming conditions expected for Memorial Day. Piers may be heavily swamped by waves. * WHERE. Mason, Oceana, Muskegon, Ottawa, Allegan and Van Buren counties. * WHEN. From Monday morning through Monday evening. * IMPACTS. Strong currents can pull swimmers into deeper water and high waves can sweep people off piers.

* WHAT. Northwest winds 10 to 20 knots with gusts up to 30 knots and waves 3 to 5 feet expected. * WHERE. St Joseph to Manistee. * WHEN. From 8 AM to 8 PM EDT Monday. * IMPACTS. Conditions will be hazardous to small craft.