From Wednesday until Oct. 21, a ¡°special heatstroke warning alert¡± will be issued when unprecedentedly dangerous heat levels are forecast for a particular prefecture, according to the Environment Ministry.?

The special alert, which is one rank above the ¡°heatstroke warning alert¡± ¡ª also to be enacted during the same period ¡ª will be issued on a prefectural level if the heat index is thought to surpass 35 degrees Celsius at most observation points in the prefecture the following day.?

The heat index, known as Wet Bulb Globe Temperature, is calculated using factors such as the temperature and humidity, as well as the surrounding thermal environment, to reflect a more realistic heat level that people experience.?

Since the alert system was implemented in April 2024, the special heatstroke warning alert has never been issued.?

In previous years, the heat index at all observation points ¡ª? not just most of them?¡ª??in a prefecture had to surpass 35 C for the warning to be issued. However, given the fact that regions situated at higher altitudes tend to have lower heat index numbers, starting this year, the ministry is excluding 24 observation points across 13 prefectures ¡ª such as Karuizawa in Nagano Prefecture and Kawaguchiko in Yamanashi Prefecture ¡ª from the criteria.?

If the special alert is issued, those in the prefecture are advised to take extra precautions to protect against the heat. School heads and event organizers, among others, should reassess certain activities such as sports practice to determine if it is safe for participants to engage in them in the outdoors. They are recommended to cancel or postpone events, or organize them online instead, if such activities could be deemed unsafe due to the heat.?

The Environment Ministry will issue the warnings at 2 p.m. on a particular day via platforms such as its website, official LINE account and email subscription service if the heat index is forecast to surpass 35 C the next day.?

The heatstroke warning alert is more common and is issued for any of the 58 regions that the ministry has designated when the heat index at one or more observation points is expected to surpass 33 C. The rate at which the alert is issued has been on the rise in recent years, with last year seeing 1,749 warnings issued compared with only 613 in 2021.?

Heatstroke continues to be a major issue in the country as summer temperatures continue to rise. Between May and September last year, a total of 1,521 people died from heatstroke across the country.?