If you wanna ski in June or July in Japan, you’d better go to Honshu (main island 本州), instead of Hokkaido. Northeast region of Honshu (Tohoku 東北地方)has by far more snow than Hokkaido, thus skiers and snowboarders move there from Hokkaido after April. Among them Gassan ski resort (月山) or Okutadami ski resort (奥只見) are both great. These ski resorts open since April till July. Due to too much snow these ski resort are closed in winter!