On Thursday afternoon, torrential rain swept across Tokyo, bringing some of the heaviest downpours the city has seen in years.
In Setagaya, and the Futako-Tamagawa area in particular—home to St. Mary’s International School—the Tamagawa River rose rapidly, spilling over onto riverside parks and nearby streets.
Side roads close to Futako-Tamagawa Station were quickly covered in muddy water, making it difficult for cars, bicycles and even pedestrians to get through.
The storm disrupted local transport as well.
The Tokyu Den-en-Toshi Line faced long delays, and the Oimachi Line suspended their service for more than four hours.
Some parts of Setagaya also experienced brief power cuts when lightning struck power lines.
The effects were also felt far beyond Setagaya.
Across the capital, rail services including several Shinkansen lines were stopped, and at Haneda Airport, ground operations were halted because of lightning, causing widespread flight delays and cancellations.
Tokyo Electric Power Company reported that more than 7,000 homes lost power at the height of the storm.
City officials urged residents throughout Tokyo to stay away from riverbanks and low-lying areas and to keep checking weather updates.
By late evening the heaviest rain had eased, but crews were still working to clear debris, inspect drainage systems and make sure the levees along the Tamagawa and other rivers remained secure.
Thursday’s storm served as a powerful reminder of how quickly sudden heavy rain can disrupt life across Tokyo, from quiet residential districts like Setagaya to major transport hubs such as Haneda Airport.
