Chesterfield, United States offers 3 beaches perfect for sunbathing, surfing, swimming, and more. Chesterfield, New Hampshire, United States, is known for Pisgah State Park, the largest state park in New Hampshire. The best time to travel to Chesterfield, United States, is in late spring (May), when the average air temperature is around 70°F (21°C) and water temperature is approximately 60°F (16°C). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!