Ashburnham, United States offers 1 beach perfect for sunbathing, surfing, swimming, and more. Ashburnham is known for Cushing Academy and the scenic Mount Watatic. The best time to travel to Ashburnham, United States, is during the summer months of June to August, when the average air temperature is around 70-80°F (21-27°C) and water temperatures in nearby lakes are typically 65-75°F (18-24°C). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!