Ma-On can led to storms that can unload over a foot of rainfall, with flooding and mudslides, upon reaching Japan. The storm will begin to turn toward the northeast through Tuesday. The earlier the turn to the north occurs, the better chance Ma-On will miss a direct landfall on southern Japan.
Greater Tokyo is unlikely to feel the worst of the storm, no matter its ultimate track. Still, rainfall will arrive by Tuesday with the worst of the storm likely from Wednesday into early Thursday.