Nagoya Rain Causes Flooding, ¥3B Damage

Nagoya, Japan, was struck by an all‑time high of 105 millimetres of rain in a single hour on Tuesday, triggering flood warnings and shutting down traffic, schools, and businesses across the city. The Japan Meteorological Agency recorded the figure, the highest hourly rainfall ever measured in the country. The deluge began in the early afternoon and lasted less than an hour, but the water rose quickly, flooding streets and basements.

Nagoya is the fourth largest city in Japan, home to over 2.3 million residents and a major industrial hub for automotive and aerospace firms. The city’s infrastructure was built for typical monsoon rains, not for the sudden, intense downpour now linked to a combination of a stalled tropical low and a heatwave that has made the region more susceptible to extreme weather. Climate‑change scientists say the frequency of such heavy rainfall events has risen in the past decade, and this record is a stark reminder of that trend.

The impact was immediate. More than 1,200 cars were stranded on the Aichi Prefectural Expressway, and several schools were closed for the rest of the day. Power outages affected roughly 10,000 households, while the city’s drainage system struggled to cope with the sudden surge. Emergency crews worked through the night to clear debris and stabilize damaged infrastructure. Local officials warned that additional rain could arrive as the weather system moves on, urging residents to stay indoors and avoid low‑lying areas. Early estimates of damage to roads, public transport, and private property exceed ¥3 billion (about $20 million).

Authorities will monitor the situation closely and may issue further evacuation orders if the forecast calls for more rain. The mayor announced a review of the city’s flood‑control plans, citing the need for upgraded drainage and new flood gates. On a national level, the government is considering stricter building codes for new developments and expanding green spaces to absorb excess water. As the city recovers, Nagoya’s experience will likely feed into Japan’s broader strategy to adapt to a hotter, wetter climate.