Waianae, United States offers 10 beaches perfect for sunbathing, surfing, swimming, and more. Waianae is known for its beautiful, less crowded beaches and authentic Hawaiian cultural experiences. The best time to travel to Waianae, United States, is from April to October, when the average air temperature ranges from 75°F to 88°F and the water temperature is around 77°F to 82°F. Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!