Seaside Park, United States offers 9 beaches perfect for sunbathing, surfing, swimming, and more. Seaside Park is known for its proximity to the famous Seaside Heights Boardwalk and the scenic Island Beach State Park. The best time to travel to Seaside Park, United States, is during the summer months of June to August, when the average air temperature is around 75°F (24°C) and the water temperature is approximately 70°F (21°C). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!