{"id":10115,"date":"2026-04-22T16:37:15","date_gmt":"2026-04-22T16:37:15","guid":{"rendered":"https:\/\/www.europesays.com\/japan\/10115\/"},"modified":"2026-04-22T16:37:15","modified_gmt":"2026-04-22T16:37:15","slug":"severe-heat-japan-adopts-official-name-for-no-longer-uncommon-40c-days-2","status":"publish","type":"post","link":"https:\/\/www.europesays.com\/japan\/10115\/","title":{"rendered":"Severe Heat: Japan Adopts Official Name for No Longer Uncommon 40\u00b0C Days"},"content":{"rendered":"<p class=\"c-series\">\n\t\t\t\t\t\t<a href=\"https:\/\/www.nippon.com\/en\/series\/japan-data\/\" rel=\"nofollow noopener\" target=\"_blank\">Japan Data<\/a>\n\t\t\t\t<\/p>\n<p>\t\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"c-cate c-cate0\" href=\"https:\/\/www.nippon.com\/en\/articlelist.html?f=ncf-category&amp;s=Environment\" rel=\"nofollow noopener\" target=\"_blank\">Environment<\/a><br \/>\n\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t\t<a class=\"c-cate c-cate2\" href=\"https:\/\/www.nippon.com\/en\/articlelist.html?f=ncf-category&amp;s=Lifestyle\" rel=\"nofollow noopener\" target=\"_blank\">Lifestyle<\/a><\/p>\n<p>\t\t\t\tApr 23, 2026<\/p>\n<p>\n\t\t\t\tThe Japan Meteorological Agency will now use the term kokushobi (\u201csevere heat day\u201d) for days when the temperature rises to 40\u00b0 Celsius or higher. Japan\u2019s record temperature of 41.8\u00b0 came in August 2025.\n\t\t\t\t<\/p>\n<p>  \t\t\t\t No Longer Extraordinary<\/p>\n<p>On April 17, the Japan Meteorological Agency officially adopted the term kokushobi (roughly \u201csevere heat day\u201d) to describe days when the maximum temperature is 40\u00b0 Celsius or higher. The Japan Weather Association, a private organization, has been using the term since 2022, which helped make it familiar enough to win a poll held by the JMA to determine the official name in Japanese.<\/p>\n<p>Official JMA Names for Types of \u201cSummer Days\u201d<\/p>\n<p>High temperatures across the country this year led to cherry blossoms going into bloom around a week to 10 days early in many locations. On April 11, a temperature of 30.3\u00b0 was recorded in the city of Shizuoka\u2019s Suruga Ward, which was the year\u2019s first \u201cmidsummer day\u201d in Japan\u2019s main island of Honsh\u016b.<\/p>\n<p>The graph below of average April temperatures in Tokyo since 1876 shows a steady rise. Until the 1980s, there were typically only one or two natsubi, when the temperature was 25\u00b0 or higher, each April, but the number has seen a rapid increase in recent years.<\/p>\n<p>In its forecast for April to June, published on March 24, the JMA predicted that due to factors including climate change, there will be high temperatures across the country. On August 5, 2025, Japan registered <a href=\"https:\/\/www.nippon.com\/en\/japan-data\/h02498\/\" rel=\"nofollow noopener\" target=\"_blank\">a new record temperature of 41.8\u00b0 in Isesaki, Gunma<\/a>. With average temperatures set to exceed typical levels in the summer of 2026 too, the agency is calling on residents to prepare for days of severe and extreme heat.<\/p>\n<p class=\"photo_box_c_v2\" style=\"width: 500px;\"><a href=\"https:\/\/www.europesays.com\/japan\/wp-content\/uploads\/2026\/04\/2991305.png\" class=\"fancybox\" rel=\"gallery\" data-libid=\"2991305\"><img decoding=\"async\" src=\"https:\/\/www.europesays.com\/japan\/wp-content\/uploads\/2026\/04\/2991305.png\" data-libid=\"2991305\" alt=\"Average April Temperatures and Number of Summer Days in Tokyo\"\/><\/a><\/p>\n<p>The JMA poll to name days with temperatures of 40\u00b0 or higher was held with 13 options from February 27 to March 29. Kokushobi (\u9177\u6691\u65e5; severe heat day) received 202,954 votes, which was more than three times as many as Ch\u014dm\u014dshobi (\u8d85\u731b\u6691\u65e5; very extreme heat day), with 65,896 votes, in second place. Among the responses to an open question in the survey were suggestions of names meaning \u201cdangerous, extreme heat day\u201d and \u201cstay-at-home day.\u201d<\/p>\n<p>Data Sources<\/p>\n<p>(Translated from Japanese. Banner photo \u00a9\u00a0Pixta.)<\/p>\n<p class=\"c-keywords\">\n\t\t\t\t\t\t\t\t\t\t\t\t <a href=\"\">climate change<\/a><br \/>\n\t\t\t\t\t \t\t\t\t\t\t\t <a href=\"\">temperature<\/a>\n\t\t\t\t\t \t\t\t\t\t\t<\/p>\n","protected":false},"excerpt":{"rendered":"Japan Data Environment Lifestyle Apr 23, 2026 The Japan Meteorological Agency will now use the term kokushobi (\u201csevere&hellip;\n","protected":false},"author":2,"featured_media":10078,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2],"tags":[2574,8,8690],"class_list":{"0":"post-10115","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-japan","8":"tag-climate-change","9":"tag-japan","10":"tag-temperature"},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/japan\/wp-json\/wp\/v2\/posts\/10115","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/japan\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/japan\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/japan\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/japan\/wp-json\/wp\/v2\/comments?post=10115"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/japan\/wp-json\/wp\/v2\/posts\/10115\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/japan\/wp-json\/wp\/v2\/media\/10078"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/japan\/wp-json\/wp\/v2\/media?parent=10115"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/japan\/wp-json\/wp\/v2\/categories?post=10115"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/japan\/wp-json\/wp\/v2\/tags?post=10115"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}