South Beloit, United States offers 1 beach perfect for sunbathing, surfing, swimming, and more. South Beloit is known for the Pearl Lake, a popular spot for outdoor recreation and water activities. The best time to travel to South Beloit, United States, is in late spring (May), when the average air temperature is around 65°F (18°C) and water temperature is approximately 55°F (13°C). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!