Oshkosh, United States offers 1 beach perfect for sunbathing, surfing, swimming, and more. Oshkosh is known for the EAA AirVenture Oshkosh, an annual air show and gathering of aviation enthusiasts. The best time to travel to Oshkosh, 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 nearby lakes is approximately 65-75°F. Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!