Japan Weather Association Releases "Netsuzero e Heat Acclimatization Frontline (Part 1)" for 2026 to Prevent Heatstroke

The Japan Weather Association (JWA), headquartered in Toshima-ku, Tokyo, and led by Chairman Kazuhiro Watanabe, promotes the "Netsuzero e" project. On April 9, 2026, the project published the "Netsuzero e Heat Acclimatization Frontline (Part 1)" on its official website (https://www.netsuzero.jp/le15-zensen). This initiative aims to inform the public about the necessity of heat acclimatization before the onset of intense summer heat. Since 2021, the project has consistently provided content on heat acclimatization. Heat acclimatization involves gradually exposing the body to heat to build resistance, typically taking several days to two weeks. The "Heat Acclimatization Frontline" provides guidance on when to begin this process, recommending activities like light exercise or warm baths. The report highlights severe heat conditions in 2025, including an average temperature deviation of +2.36℃ from June to August (a record high, surpassing +1.76℃ in 2023/2024). A new domestic record high of 41.8℃ was recorded in Isesaki City, Gunma Prefecture, on August 5, 2025. Additionally, 30 locations observed temperatures of 40℃ or higher, and there were 9,385 extreme heat days (35℃ or higher) nationwide from June to August, the most since 2010. For April 2026, nationwide temperatures are predicted to be higher than average, necessitating caution against "spring heatstroke." The project advises starting heat acclimatization in April-May and preparing for summer by checking air conditioners and gathering heat prevention items. Further information will be shared on the project's website and X account (@netsuzero2013). A second "Heat Acclimatization Frontline" report is planned for early June. A downloadable "Heat Acclimatization Point Manual" is also available at https://www.netsuzero.jp/images/learning/le15/download_pdf01_2026.pdf.