Three Central Japan Cities Hit 40C, Marking First Kokushobi as Heat Kills 3
Updated
Updated · Kyodo News Plus · Jul 21
Three Central Japan Cities Hit 40C, Marking First Kokushobi as Heat Kills 3
3 articles · Updated · Kyodo News Plus · Jul 21
Summary
Tajimi, Gujo and Toyoda reached 40.3C, 40.0C and 40.1C on Tuesday, triggering Japan's first officially recognized "kokushobi" since the weather agency coined the 40C warning term in April.
A high-pressure system that spread across much of Japan around Sunday heated both surface and upper air, pushing temperatures near 40C elsewhere, including 39.7C in Nagoya and 38.6C in Kumagaya.
Three heat-related deaths have already been reported: two men found collapsed outdoors on Monday in Kanagawa and Niigata later died, and an 80s woman in Mitsuke died of heatstroke Tuesday after being found at home.
Across 914 observation points, 731 logged highs of at least 30C by 3 p.m. Tuesday, while 272 recorded "moshobi" conditions below the new 40C "kokushobi" threshold.
The Japan Meteorological Agency expects dangerous heat to persist from Wednesday and urged precautions against heat-related illness.
Japan has new heat alerts, but are its cities truly ready for a future where 40°C summers are the new normal?
With 'cruelly hot' days now official, is Japan's culture of endurance being replaced by a new reality of climate adaptation?
As extreme heat threatens Japan's iconic rice crops, how will the nation's food security and culinary traditions be forced to adapt?
"Japan’s 40°C ‘Kokushobi’ Days: Extreme Heatwave Forces New Health Alerts and Societal Change"
Overview
In July 2026, Japan experienced its first 'kokushobi' days, a new term officially adopted in April to describe days when temperatures reach or exceed 40°C—now a frequent occurrence. This change reflects a clear shift in Japan’s climate, making previous heat categories insufficient. The term was chosen through a public survey with nearly half a million responses, showing widespread concern about rising temperatures. The introduction of 'kokushobi' and strong public engagement highlight how Japan is recognizing and responding to its escalating heat crisis, marking a significant moment in the country’s adaptation to extreme weather.