Environment Japan issues heatstroke alerts for record 19 prefectures

[thomas]

Japan's environment and weather authorities have issued heatstroke alerts for a record 19 prefectures on 15 July, warning that dangerously high temperatures pose an extremely high risk of heat-related illness. The alerts also mark the first issued this year for the Kanto region.

The Ministry of the Environment and the Japan Meteorological Agency issued the warnings for Ibaraki , Gunma, Saitama, Tokyo, Chiba, Kanagawa, Nagano, Yamanashi , Aichi, Mie, Niigata, Toyama, Ishikawa, Wakayama, Tokushima, Ehime, Nagasaki, Miyazaki and Kagoshima prefectures.

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Authorities are urging people in areas covered by the alerts to pay closer attention than usual to indoor temperature and humidity, use air conditioners and other cooling equipment appropriately, and spend time in cooler environments. People are also advised to take frequent breaks and replenish fluids and salt. Officials said the heat could cause harm to human health and urged people to protect themselves from the extreme conditions. They also called on people to consider canceling or postponing exercise, work and other activities outdoors or in indoor spaces without air conditioning wherever possible, warning that strenuous exercise should be avoided. Authorities further urged people to check on those especially vulnerable to heat, including elderly people, people with disabilities and small children.

Heatstroke Alerts Issued for Record 19 Prefectures

Japan

newsonjapan.com

 

[thomas]

Severe heat gripped much of Japan on 20 July as a Pacific high-pressure system covered large parts of the country, pushing central Tokyo to 35 degrees Celsius for the first time this year. The Japan Meteorological Agency said unusually high temperatures were likely to continue across eastern and western Japan until around 24 July. It urged people to take precautions against heatstroke and other heat-related health problems.

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The summer Pacific high spread across the main island of Honshu, while warm air of at least 21 degrees Celsius moved into the region at an altitude of around 1,500 metres. Strong early-day sunshine caused temperatures to climb quickly.

The AMeDAS observation station at Kitanomaru Park in Tokyo's Chiyoda Ward recorded 35 degrees at 11:09 a.m., marking the capital's first extremely hot day of the year, a designation used when the daily maximum temperature reaches 35 degrees or higher. Other parts of the Kanto region also experienced intense heat. By 11 a.m., the temperature had reached 35.8 degrees in Hatoyama, Saitama Prefecture, and 35.4 degrees in Kiryu, Gunma Prefecture.

Tokyo Swelters Through First 35 C Day of the Year

Severe heat spread across Japan on July 20 as a Pacific high-pressure system covered much of the country, pushing the temperature in central Tokyo to 35 degrees Celsius for the first time this year.

newsonjapan.com

The good thing: the rainy season is officially over!

The mercury hit 39.4 C in Koshu, Yamanashi Prefecture, west of Tokyo, while 36.1 C was logged in central Tokyo, according to the Japan Meteorological Agency. The rainy season ended about 22 days later than last year in the Kanto-Koshin region, including Tokyo, and about 23 days later in the Tokai region centred on Nagoya in Aichi Prefecture.

Rainy season over in Tokyo, mercury hits 35 C as "extremely hot" day logged

The rainy season has likely ended in regions including Tokyo and Nagoya, the weather agency said Monday, with the Japanese capital marking the first "extremely hot" day of the year as the mercury hit 35 C.

english.kyodonews.net

 

[thomas]

Kuwana in Mie Prefecture reported 40.6°C Celsius yesterday, the highest temperature ever measured in Japan.

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Kuwana in Mie Prefecture recorded 40.6°C on Thursday, the highest temperature in Japan so far this year, as a strong high-pressure system combined with hot downslope winds to bring dangerous heat to wide areas of the country. Temperatures reached 40°C or higher at four observation points; a total of 298 locations recorded highs of at least 35°C. Kuwana logged the day's peak of 40.6°C at 10:24 a.m. Other places where temperatures topped 40°C included Mino and Tajimi in neighbouring Gifu Prefecture. Television footage from Kuwana showed thermometers installed beside buildings climbing above 40°C under intense sunshine. In Gifu City, another thermometer exposed to direct sunlight appeared to be nearing 45°C.

Why Kuwana Reached a Record 40.6 Degrees

Kuwana in Mie Prefecture recorded 40.6 degrees Celsius, the highest temperature anywhere in Japan this year, as a powerful high-pressure system and hot downslope winds combined to produce dangerous heat across a wide area.

newsonjapan.com

We're getting 38°C here in Kanto today. I have to admit that my daily bike commute has never been that challenging.

 

[thomas]

How to beat the heat in Japan: in a human-sized freezer.

https://edition.cnn.com/2026/07/22/world/video/japan-human-fridge-extreme-heat-hnk-vrtc-digvid