Japan Meteorological Agency Adopts 'Kokushobi' for Days Exceeding 40°C
The Japan Meteorological Agency (JMA) announced on April 17, 2026, the adoption of a new weather term, "kokushobi," to designate days with temperatures reaching 40 degrees Celsius or higher. Literally translating to "cruelly hot day," this terminology will be integrated into official weather forecasts starting this summer. The initiative aims to enhance public safety warnings by clearly communicating the extreme danger associated with such intense heat, responding to a trend of record-breaking temperatures in recent years. Prior to this announcement, Japan lacked a specific classification for temperatures above 35°C, which were labeled "moshobi" (extremely hot day). The new term was selected through a month-long online poll, where "kokushobi" secured over 200,000 votes, significantly outperforming other candidates. This decision aligns with data showing that Japan has experienced at least one day exceeding 40°C annually since 2018, including a national record of 41.8°C set in Isesaki in August 2025. The Japan Weather Association had already been using the term independently since 2022.
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Japan Meteorological Agency Adopts 'Kokushobi' for Days Exceeding 40°C
The Japan Meteorological Agency (JMA) announced on April 17, 2026, the adoption of a new weather term, "kokushobi," to designate days with temperatures reaching 40 degrees Celsius or higher. Literally translating to "cruelly hot day," this terminology will be integrated into official weather forecasts starting this summer. The initiative aims to enhance public safety warnings by clearly communicating the extreme danger associated with such intense heat, responding to a trend of record-breaking temperatures in recent years. Prior to this announcement, Japan lacked a specific classification for temperatures above 35°C, which were labeled "moshobi" (extremely hot day). The new term was selected through a month-long online poll, where "kokushobi" secured over 200,000 votes, significantly outperforming other candidates. This decision aligns with data showing that Japan has experienced at least one day exceeding 40°C annually since 2018, including a national record of 41.8°C set in Isesaki in August 2025. The Japan Weather Association had already been using the term independently since 2022.
The Mainichi