Scorching heat in Isesaki, Japan: Mercury climbs to an unprecedented 41.8 degrees Celsius, breaking the previous record.
Record-Breaking Heatwave Hits Japanese Cities
Japan is currently experiencing an unprecedented heatwave, with cities like Isesaki, Hatoyama, Kiryu, and Maebashi setting new temperature records. The intense subtropical high-pressure system and a West Pacific marine heatwave have been the primary causes of this prolonged and severe heatwave.
In early August 2025, Japan saw multiple temperature records being set. Isesaki, a city in Gunma Prefecture, recorded a record-breaking high of 41.8 degrees Celsius on Tuesday, surpassing the previous record of 41.2 degrees set in Tamba, Hyogo Prefecture last week. This was also the highest temperature ever recorded in Japan.
The cities of Hatoyama, Kiryu, and Maebashi, all in Gunma Prefecture, also saw record-breaking temperatures. On the same day, Hatoyama reached 41.4 degrees Celsius, Kiryu reached 41.2 degrees Celsius, and Maebashi reached 41.0 degrees Celsius. These temperatures are among the highest ever recorded in their respective prefectures.
The double layer of the Pacific anticyclone and the Tibetan high-pressure system has been responsible for the persistence of this heatwave. This summer, the Japanese archipelago has been under the influence of this system, leading to a very dry climate and prolonged heat.
On Tuesday, temperatures of 40.0 degrees or higher were recorded at 14 locations across five prefectures. This is the first time that such temperatures have been recorded at this many locations. The previous record for the highest single-day total of temperatures of 40.0 degrees or higher was broken on this day.
This extreme heatwave is not limited to these cities. The record high temperatures in Hatoyama, Kiryu, and Maebashi are part of the highest single-day total of temperatures of 40.0 degrees or higher since records began. This is the highest single-day total of such temperatures since records began.
These record-breaking temperatures are a stark reminder of the impact of climate change on our weather patterns. As we continue to experience such extreme weather events, it is crucial that we take steps to mitigate our carbon emissions and adapt to a changing climate.
[1] Climate Change: The Impact on Japan's Weather
[2] Japan's Record-Breaking Heatwave: What You Need to Know
[3] The Science Behind Japan's Record-Breaking Heatwave
[4] Japan's Summer of 2025: The Hottest Ever
[1] A collection of environmental-science photographs depicting the effects of climate change on Japan's weather could serve as a compelling display at the upcoming United Nations conference.
[2] In the science classroom, discussing Japan's record-breaking heatwave with students, a relevant and timely topic for exploring meteorological and climate patterns.
