Weather Report: Dangerous Heat is Imminent in Kanto, Tokyo!
Latest Weather Alert by Sayaka Ikeda
Tokyo experiences first consecutive hot days this June
Dangerously hot weather continues in the Kanto region. Tokyo ‘s central area has been experiencing a series of extremely hot days with maximum temperatures exceeding 35°C for four consecutive days from June 25 to 28. This is the first time in observed history that Tokyo has had two or more consecutive extremely hot days in June. The record for the hottest day is still expected to be broken today with a maximum temperature of 36°C. In addition, the inland areas of the Kanto region will once again experience a temperature of 40°C.
In addition, the inland areas of the Kanto region are likely to exceed 40°C (104°F) again, and record-breaking heat is expected.
The heat will peak today and tomorrow, and will continue to be dangerously hot throughout the week.
Heat stroke alerts have been issued for Ibaraki, Tochigi, Gunma, and Saitama Prefectures today. Tomorrow, Tokyo Metropolitan Government may issue its first heat stroke alert of the year.
Due to the continuous heat, many places will have tropical nights with temperatures not falling even at night. Heat precautions should be taken both day and night.
High pressure strengthens and the rainy season front moves northward. This will be the earliest end of the rainy season in statistical history.
The Japan Meteorological Agency announced that the rainy season ended on June 27 in southern Kyushu, Tokai, and Kanto Koshin regions, and on June 28 in northern Kyushu, Chugoku, Shikoku, Kinki, and Hokuriku regions. The Kanto Koshin region had the shortest rainy season at 21 days.
(The date will be reviewed and the final date will be announced on September 1 every year.)
This year, the summer high-pressure system (Pacific High) was forecasted to strongly extend to the north, and this high-pressure system has suddenly strengthened its power and pushed the rainy season up to northern Japan.
Warm air is flowing in from the south toward this front, and temperatures are rising in western and eastern Japan, and the summer high-pressure system is making it easier for temperatures to rise due to the sunshine.
Although it is only June, the weather is already like midsummer.
Heat Stroke Alert will be issued when the “Heat Index” reaches 33°C or higher.
Since 2021, the Japan Meteorological Agency has been issuing Heat Stroke Alerts for the entire country on the evening before or early morning of days when the risk of heat stroke is expected to be extremely high, on a prefectural basis.
This heat stroke alert is issued when the heat index (WBGT ) is expected to reach 33°C or higher, which is based on the heat index ( WBGT ) that takes humidity and heat from the sun’s reflection into account, in addition to temperature. The “heat index” is an indicator of the risk of heat stroke, consisting of temperature, humidity, and radiant heat (sunlight, etc.).
You can find out the situation in your area from the following website.
Click here for the Ministry of the Environment’s Heat Stroke Prevention Information Website.
Consecutive hot days: In 2010 and 2018, the Kanto Koshin region had consecutive hot days.
The Japan Meteorological Agency forecasts that this summer will be hot nationwide due to the La Niña phenomenon.
A similar phenomenon to this year’s occurred in the summer of 2010, when Hokkaido recorded the nation’s first extremely hot day of the year on June 26, and also observed abnormally high temperatures with maximum temperatures exceeding 15°C above normal.
Koshigaya City, Saitama Prefecture, recorded 18 consecutive hot days from August 21 to September 7, and Koga City, Ibaraki Prefecture, Saitama City, and Nerima Ward, Tokyo, 17 consecutive hot days. The annual number of tropical nights was 56 in Tokyo (average: 27.8 days). The Japan Meteorological Agency recognized this heat wave as a once-in-30-years extreme weather event.
According to the Ministry of Health, Labor and Welfare, the number of deaths due to heat stroke that year was 1,718 nationwide, including 272 in Tokyo and 124 in Saitama Prefecture. The number of deaths exceeded 1,000 for the first time in statistical history.
The unusually early end of the rainy season was due to the strong overhang of the Pacific High Pressure System and the early push-up of the rainy season front, which led to a similar phenomenon in 2018, with 54,220 people being transported to hospitals for emergency medical treatment due to heat stroke in July across Japan, and 133 people dying. The number of fatalities in July exceeded the 95 fatalities in July 2010.
Heat Stroke Prevention When a “Heat Stroke Alert” is issued
The JMA’s forecast temperatures are based on temperatures in well-ventilated places out of direct sunlight. In the city, temperatures will be higher in sunny places, and children in particular should be more careful than adults because they will be affected by the heat from the asphalt closer to the ground.
- □Use air conditioners appropriately.
- □Refrain from going outside as much as possible.
- □Call out to those who are at high risk of heat stroke
- □In principle, stop or postpone exercise outside.
- □Check the heat index
- Drink 1.2 liters of water per day before getting thirsty.
In addition, the temperature inside a closed car can rise in a short period of time and reach over 50℃. It is dangerous to leave children unattended in a car for even a short period of time.
According to the Ministry of the Environment and the Ministry of Health, Labor and Welfare, 90% of the people who die of heat stroke in the 23 wards of Tokyo are elderly people, and 90% of them suffer heat stroke indoors. There are various reasons for heat stroke, such as “it is a waste of time to use the air conditioner for a long time” or “I don’t like the breeze from the air conditioner.”
In addition, because the high temperatures continue, there are likely to be places where the temperature does not drop even at night and tropical nights continue. It is said that we sweat a cupful of sweat while we sleep, so we should drink water before going to bed and use the air conditioner effectively to prevent heat stroke at night as well.
Since this is the time of year when the body is not yet accustomed to the heat, take extra precautions than usual to avoid heat stroke.
Sayaka Ikeda is from Hiroshima Prefecture and became a certified meteorologist in 2015. She has appeared on “Asaichi” (NHK Sogo), “Jane Sue: Life is Dance,” “Tamamusubi,” “Ogigami Chiki Session,” “5 O’clock News, Weather Report,” “Takayuki Hasumi: Matomete! Saturday” and “Saturday Wide Radio TOKYO Nights’ Chaki-Chaki-Daihoso” (TBS Radio Tuesdays and Saturdays), providing weather information.
Reporting and writing： Izumi Nakagawa
