cross-posted from: https://lemmygrad.ml/post/11362069
Archive link: https://archive.ph/KDutA
Japan has unveiled a new name for days that reach 40C (104F) or above, after the country experienced its hottest summer on record last year. The term - kokushobi - has been translated as “cruelly hot”, “brutally hot” or “severely hot” day by Japanese and international media. The name emerged as the most popular in a national online survey, with “super extremely hot day” in second place. Extreme weather events like heatwaves are becoming more common and more intense around the world, fuelled by human activities such as the burning of fossil fuels.
The description, introduced by Japan’s Meteorological Agency (JMA) on Friday, uses koku - meaning harsh or cruel - to describe the heat, the Japan Times newspaper reported. The survey was conducted in February and March and received roughly 478,000 responses, in which people picked their preferred term among 13 options to describe the hottest day. Japan already has terms for days over 25C, 30C and 35C.
The new word for even hotter weather comes after record-shattering heat hit Japan last year. Summer 2025 was the hottest since records began in 1898 - with average temperatures nationwide 2.36C above average. Temperatures reached 40C-plus on nine days between June and August, with a new national peak of 41.8C in the city of Isesaki. The cumulative number of extremely hot days also surpassed the previous record set in 2024. For example, Tokyo recorded 25 days over 35C, compared with an average of just 4.5 days. Kyoto logged 52 days above the same temperature, compared with an average of 18.5 days. This summer, JMA forecasts a high probability of above-normal temperatures in Japan from June to August.
The article makes it seem a bit more mystical than it actually is. 酷暑 (kokusho) isn’t a neologism or anything—it’s a normal word for “severe heat”, and you can find it in Japanese-English or Japanese-Japanese dictionaries. All they’re doing is sticking the kanji for “day” on the end to make it “[brutally hot]-[day]”. The runner-up simply adds the intensifier 超 to the term for 35+ C° days (猛暑日).
Here are the full results[1] of the poll, all of which employ existing words for extreme heat, although some of the ones listed in the “others” section after the quantified results get a bit more creative (such as サウナ日 (“sauna day”) and 自宅待機日 (“staying at home day”)):
最高気温が 40℃以上の日の名称に関するアンケート結果
今般の名称検討にあたって行われたアンケート結果は以下のとおりです。
実施期間： 令和 8 年 2 月 27 日（金）～3 月 29 日（日）
総回答数： 478,296候補名 得票数 酷暑日 202,954 超猛暑日 65,896 極暑日 25,638 炎暑日 22,292 烈暑日 21,930 激暑日 20,282 厳暑日 9,219 熱暑日 8,782 甚暑日 4,595 劇暑日 4,396 大暑日 3,341 盛暑日 1,478 繁暑日 865 また、「その他」のご意見として、以下のような名称案も寄せられました。 「汗日暑日暑」、「灼熱日」、「激アツ日」、「危険猛暑日」、「自宅待機日」 「極猛暑日」、「サウナ日」、「鬼暑日」、「沸騰日」、「熱盛日」など
なお、「酷暑日」は一般財団法人日本気象協会において日最高気温 40℃以上 の日を指す用語として 2022 年から独自に使用されています。