Oostburg, United States offers 4 beaches perfect for sunbathing, surfing, swimming, and more. Oostburg, Wisconsin, United States, is known for its proximity to the scenic Lake Michigan shoreline and the nearby Kohler-Andrae State Park. The best time to travel to Oostburg, United States, is during the summer months of June to August, when the average air temperature is around 70-80°F and the water temperature in Lake Michigan is approximately 60-70°F. Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!