West Islip, United States offers 1 beach perfect for sunbathing, surfing, swimming, and more. West Islip, New York, United States, is known for its proximity to the scenic Robert Moses State Park and the historic Sagtikos Manor. The best time to travel to West Islip, United States, is during late spring to early summer (May to June) when the average air temperature is around 65-75°F and the water temperature is approximately 60-65°F. Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!