Minamiosumi, Japan offers 6 beaches perfect for sunbathing, surfing, swimming, and more. Minamiosumi is known for Cape Sata, the southernmost point of Kyushu, Japan. The best time to travel to Minamiosumi, Japan, is from April to June, with average air temperatures around 20-25°C (68-77°F) and water temperatures around 20-23°C (68-73°F). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!