Bay Saint Louis, United States offers 4 beaches perfect for sunbathing, surfing, swimming, and more. Bay Saint Louis is known for its Old Town Bay St. Louis, the Alice Moseley Folk Art and Antique Museum, and the Bay St. Louis Beach. The best time to travel to Bay Saint Louis is in the spring (March to May) when the average air temperature is around 70-80°F and the water temperature 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!