Rosslyn, Australia offers 3 beaches perfect for sunbathing, surfing, swimming, and more. Rosslyn, Queensland, Australia, is known for its proximity to the Great Keppel Island and the Capricorn Coast. The best time to travel to Rosslyn, Australia, is from September to November, with average air temperatures around 20-25°C (68-77°F) and water temperatures around 22°C (72°F). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!