Tainai, Japan offers 1 beach perfect for sunbathing, surfing, swimming, and more. Tainai is known for the Tainai Kogen Ski Resort and the Tainai Lake, which are popular attractions for tourists. The best time to travel to Tainai, Japan, is in late spring (May), when the average air temperature is around 18°C (64°F) and the water temperature is approximately 15°C (59°F). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!