Windham, United States offers 3 beaches perfect for sunbathing, surfing, swimming, and more. Windham, Maine, United States, is known for its proximity to Sebago Lake and outdoor recreational activities. The best time to travel to Windham, United States, is during the summer months of June to August, when the average air temperature is around 70-80°F and water temperature in nearby lakes is approximately 65-75°F. Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!