News Discussion

Japan Shatters Multiple Heat Records as Over 10 Locations Hit 40°C

A high-pressure system is bringing clear skies and intense heat to wide areas of Japan. On August 5, warm air pushed temperatures even higher across much of the country.

Isesaki City in Gunma Prefecture set a new national record with a temperature of 41.8 °C (107.2 °F). Across the Kanto region, more than 10 locations reached 40 °C (104 °F) or higher — the most ever recorded in a single day.

Weather Patterns

Warm air was pulled in by a low-pressure system moving east near Hokkaido. In Kanto a phenomenon called the "Foehn effect" likely took place. This occurs when winds heat up as they descend over mountains. Located on the eastern side of Honshu, Japan's largest island, the Kanto region is made up of seven prefectures: Chiba, Gunma, Ibaraki, Kanagawa, Saitama, Tochigi, and Tokyo.

Rising Temperatures in Sapporo

Amid this record-breaking heat, even Hokkaido recorded its highest average July temperature ever, which has driven a surge in demand for air conditioners. However, the region has fewer installation contractors than the main island of Honshu, making it hard to keep up with the growing need.

According to the Japan Meteorological Agency, Sapporo’s average temperature in July 2025 was 25.8 °C (78.4 °F), 2.5 °C (4.5 °F) higher than in July 2024.

Since 2021, July temperatures in Hokkaido have generally hovered around 23 °C (73.4 °F). Before that, they usually stayed between 20 °C (68 °F) and 22 °C (71.6 °F). The data shows a sharp rise in recent years.

1. 1. intense　（痛み・暑さなどが）強烈な、激しい
   I have an intense pain in one of my teeth.
2. 2. region　地域、地方
   The Tohoku region is going to have cooler temperatures toward the end of the week.
3. 3. descend　（山などを）降りる
   We descended from the mountain using our climbing ropes.
4. 4. demand　需要、要望
   The demand for avocados is high these days.
5. 5. sharp　（変化などが）急激な、著しい
   Recently, there has been a sharp drop in the number of visitors to Hawaii.

1. 1. Which city has the new record for the hottest temperature in Japan? What was the temperature?
2. 2. What is the Foehn effect?
3. 3. What effect has the hot weather had on air conditioning in Hokkaido?
4. 4. What effects is the record heat having on life in your area? Consider the effects on businesses, farms, animals, and individuals.
5. 5. How are you changing your daily routine to survive the intense heat?

暖かい空気の影響で、8月5日も日本の広い範囲で気温が上がり、群馬県伊勢崎市の最高気温が41・8度になり、国内最高記録を更新した。関東各地で40度に達する地点が10以上となり、地点数としても観測史上最多となった。熱中症対策が必要だ。

北海道付近を東に進む低気圧に向かって暖かい空気が流れ込んだ。関東では風が山を越える際に高温になって吹き下ろす「フェーン現象」が発生したとみられる。

北海道でも7月の平均気温が観測史上最高を更新しており、エアコンの需要が増加している。しかし設置工事ができる施工業者が本州と比べて少なく、普及の足かせになりかねない状況だ。

気象庁によると、今年7月の札幌市の平均気温は25・8度で前年同月から2・5度上昇。2021年以降は23度台が続いていたが、それ以前はおおむね20～22度で推移しており、近年になって気温が急激に上昇していることがわかる。