Japan records its first ‘cruelly hot day’ as cities swelter in 40-degree heat
In April Japan coined new term kokushobi for days above 40C as country advises workers to wear shorts to the office to cope with stifling heat Japan logged its first official kokushobi or “cruelly hot day” on Tuesday since the new term for when temperatures...
Japan has recorded its first official “cruelly hot day” after temperatures climbed above 40 degrees Celsius in central areas of the country, according to a monitored public feed citing The Guardian World.
The Japan Meteorological Agency introduced the term kokushobi in April to describe days when the mercury rises above 40C, a threshold that officials say reflects a heat risk that is no longer rare. On Tuesday, Japan logged its first such day since the designation was created.
Three cities in central Japan reached the extreme mark: Gujo and Tajimi in Gifu prefecture, and Toyota in Aichi prefecture. Gujo hit 40C, while Toyota reached 40.1C. The feed reported that both figures were all-time highs for the weather stations in those cities.
The new label was created as Japan continues to face intense summer heat that has pushed some temperatures into territory once seen only as exceptional. The feed said the agency’s aim is to warn the public about the dangers posed by increasingly common severe heat.
Japan has also been advising workers to adapt to the conditions, including allowing shorts in office settings as a way to cope with the stifling weather.
The latest readings add to growing concern over how sharply temperatures can rise in parts of the country during summer, particularly in inland prefectures such as Gifu and Aichi. The new kokushobi designation underscores the extent to which heat extremes are now part of the seasonal picture.
This report is based on a monitored public feed and is attributed to The Guardian World. Source: The Guardian World - https://www.theguardian.com/world/2026/jul/22/japan-heat-kokushobi-cruelly-hot-40c-weather
