Yankton, United States offers 3 beaches perfect for sunbathing, surfing, swimming, and more. Yankton is known for its scenic Missouri River views and outdoor recreational activities. The best time to travel to Yankton, United States, is in late spring or early fall when the average air temperature is around 60-75°F and the water temperature in the Missouri River is approximately 60-70°F. Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!