Millcreek, United States offers 1 beach perfect for sunbathing, surfing, swimming, and more. Millcreek, Pennsylvania, United States, is known for Presque Isle State Park, a popular destination for outdoor recreation and natural beauty. The best time to travel to Millcreek, United States, is during late spring to early fall (May to September) when the average air temperature ranges from 60°F to 85°F, and water temperatures in nearby lakes and rivers are typically between 50°F and 70°F. Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!