Heavy rain and flooding in Tokyo

The Greater Tokyo Area will experience several days of moderate to heavy rainfall through the first part of the weekend.
A slow-moving storm system has already brought a swath of 100-200 mm (4-8 inches) of rain to southern Japan, including the far northern Ryukyu Islands, eastern Kyushu, Shikoku and southern Honshu. Local rainfall amounts have exceeded 380 mm (15 inches) across parts of southern Shikoku and Honshu.

Heavy rainfall from Wednesday through Thursday totaled more than 500 mm (20 inches) in the city of Owase, in southern Honshu.
The heavy rain pushed into Tokyo on Friday and will continue through Saturday. More than 150 mm (6 inches) have already fallen in the city with local amounts approaching 200 mm (8 inches)

http://www.accuweather.com/en/weather-news/heavy-rain-and-flooding-tokyo/28145454