Tokyo heat hospitalisations hit record as Japan faces severe heatwave

Tokyo recorded 453 heat-related hospitalisations on Wednesday, the highest daily count since records began in 2010, the Tokyo Fire Department said, as Japan experienced a severe heatwave. One person died in Tokyo prefecture, four people were in critical condition and 18 were in a serious condition, a fire brigade spokesman said.

The spokesman said emergency services were deployed a record number of times for the day, reaching a 63-year high. He urged people to stay hydrated and use air conditioners, and said the number of patients appeared to rise as temperatures rose.

Tokyo prefecture is home to around 14 million people.

Officials said 116 people were taken to hospital on Wednesday for heat-related conditions across Aichi, the central region that includes Nagoya.

The Japan Meteorological Agency said four locations recorded temperatures above 40C on Wednesday: one in Mie, two in Gifu and one in Shizuoka. At least six other places recorded 39.8C.

Japan introduced a new term this year, “kokushobi”, meaning “cruelly hot day”, to describe heat above 40C. The term was designed to draw more public attention to heat-related warnings, but it does not trigger any official nationwide measures.

Heatstroke alerts were in place across almost the whole country. Emergency officials said Wednesday that at least 14 people had died from heat-related causes in the past week. The Fire and Disaster Management Agency said almost 11,000 people sought emergency medical care in Japan during that period, and 14 were pronounced dead on arrival.

The agency said people should regard the extreme heat as a disaster. It said temperatures had been rising since mid-July and severe heat was expected to continue nationwide.

Scientists say human-induced climate change is increasing the frequency and intensity of extreme heat events in Japan and elsewhere. Japan had its hottest summer on record last year. Its highest recorded temperature was 41.8C, measured on 5 August 2025 in Isesaki, north of Tokyo.