South Mission Beach, Australia offers 3 beaches perfect for sunbathing, surfing, swimming, and more. South Mission Beach, Queensland, Australia, is known for its proximity to Dunk Island and the Great Barrier Reef. The best time to travel to South Mission Beach, Australia, is from May to September, when the average air temperature is around 25°C (77°F) and the water temperature is approximately 23°C (73°F). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!