Wonnerup, Australia offers 3 beaches perfect for sunbathing, surfing, swimming, and more. Wonnerup, Western Australia, Australia, is known for the Wonnerup House, a historic homestead managed by the National Trust. The best time to travel to Wonnerup, Australia, is during the summer months of December to February, when the average air temperature is around 25°C (77°F) and the water temperature is approximately 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!