Oak Harbor, United States offers 26 beaches perfect for sunbathing, surfing, swimming, and more. Oak Harbor is known for Deception Pass State Park and the Naval Air Station Whidbey Island. The best time to travel to Oak Harbor, United States, is during the summer months of June to August, when the average air temperature is around 65-75°F and the water temperature is approximately 55-60°F. Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!