Grand Island, United States offers 2 beaches perfect for sunbathing, surfing, swimming, and more. Grand Island is known for Beaver Island State Park and Fantasy Island amusement park. The best time to travel to Grand Island, United States, is in late spring (May), when the average air temperature is around 65°F (18°C) and the water temperature is approximately 55°F (13°C). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!