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Extreme heat and weather alerts in Japan

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2026-08-26 10:06 UTC → 2026-08-26 11:18 UTC · added ~~removed~~

Japan continues to face significant heatstroke risks and extreme temperatures. In Fukuoka Prefecture, authorities issued heatstroke alerts for late August, with temperatures in Kurume expected to reach 38 degrees Celsius and dangerous Wet Bulb Globe Temperature (WBGT) indices reported in Omata. To mitigate such risks, some local events, such as the Saga Castle Town Saka no Kuni Festival, have moved their schedules from August to May. Forecasts from the Japan Meteorological Agency indicate that high temperatures are likely to persist through November, driven by the El Niño phenomenon, which is expected to cause a slow progression of seasons. Recent updates confirm that high temperatures will likely persist through September and October, delaying the arrival of autumn. In addition to ongoing heatstroke alerts in Kumamoto and Tochigi Prefecture—where several locations have reached “dangerous” heat index levels—new weather threats are emerging. An autumn rain front is expected to move south toward Honshu, acting as a “rain cloud production line.” This front is predicted to bring heavy rain, particularly along the Sea of Japan coast, increasing the risk of river flooding and road inundation. Recent developments show the heat intensity escalating in Fukuoka, where temperatures in Hakata reached a record 40.4 degrees Celsius, marking the first time Fukuoka City has recorded a “scorching day” above 40 degrees. Furthermore, parts of Hokkaido and the Sea of Japan face risks of severe thunderstorms, lightning, and tornadoes due to high sea surface temperatures and unstable atmospheric conditions. The public health impact has been severe; in July, over 41,000 people were hospitalized due to heatstroke, with at least 79 confirmed deaths. More than 60 percent of those hospitalized were aged 65 or older.

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