Blue Spring, United States offers 2 beaches perfect for sunbathing, surfing, swimming, and more. Blue Spring, Kentucky, United States, is known for the Mammoth Cave National Park. The best time to visit Blue Spring, United States, is from November to March when the average air temperature is around 70°F (21°C) and the water temperature remains a constant 72°F (22°C). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!