Oma, Japan offers 1 beach perfect for sunbathing, surfing, swimming, and more. Oma is known for its Oma Maguro, a premium bluefin tuna highly sought after in the culinary world. The best time to travel to Oma, Japan, is in late spring (May), when the average air temperature is around 15°C (59°F) and the water temperature is approximately 12°C (54°F). Sandee provides detailed maps, photos, and reviews from fellow beachgoers to help you Choose Your Beach™ and plan your perfect beach vacation!