Tropical storm Yun-yeung is approaching central and eastern Japan. The storm is expected to make landfall Friday afternoon, but some areas are already under alert.
Japan's weather agency reported Yun-yeung was south-southwest of Shizuoka Prefecture Friday morning. The storm will likely move north throughout the day.
Heavy rain has already triggered mudslide alerts in the Izu Islands and in Chiba prefecture. A record high of more than 200 millimeters of rain fell in just six hours in Chiba prefecture's Mobara City.
Meanwhile, in Tokyo, rain poured in from the ceiling at Shinjuku Station. Staff were on the scene trying to contain the water.
Thunderstorms are forecast for the central region of Tokai through Friday night. They're also expected in the eastern region of Kanto-Koshin and the northeastern region of Tohoku through Saturday.
Those areas could see up to 250 millimeters of rain in the next 24 hours alone.
Weather officials are calling on people to watch out for mudslides, flooding in low-lying areas and swollen rivers. Strong winds, high waves and lightning are also expected.