Tsurushi Clouds Japan -- A rare anvil or hat-shaped cloud appeared near Mount Fuji after a strong typhoon swept through Japan. The cloud, called "tsurushi-gumo," or hanging cloud, was seen on Wednesday morning. The phenomenon occurs after tropical storms or when winds around Mount Fuji become strong. But experts say such clouds rarely appear at this time of the year. The cloud disappeared after about 30 minutes when the sky became overcast.