Mordialloc, Australia offers 1 beach perfect for sunbathing, surfing, swimming, and more. Mordialloc is known for Mordialloc Beach and the Mordialloc Pier. The best time to travel to Mordialloc, Australia, is during the summer months of December to February, when the average air temperature is around 20-25°C (68-77°F) and the water temperature is approximately 18-21°C (64-70°F). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!