Tiwi Islands, Australia offers 2 beaches perfect for sunbathing, surfing, swimming, and more. Tiwi Islands, Northern Territory, Australia, is known for its unique Aboriginal culture and the annual Tiwi Islands Football Grand Final and Art Sale. The best time to visit the Tiwi Islands, Australia, is from May to September, when the average air temperature is around 25-30°C (77-86°F) and the water temperature is approximately 26°C (79°F). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!