Korea issues 1st-ever heat wave emergency warning for southeast

Pedestrians walk along a road in Yeouido, Seoul, Sunday, under a heat wave warning issued for the city. Yonhap

A heat wave emergency warning — the highest alert level — was issued for Gyeongsan and Pohang in North Gyeongsang Province at 10 a.m. Sunday, marking the first activation of the alert since it was introduced under the revised advisory system last month.

The warning is issued when a region that has already had a perceived temperature of 35 degrees Celsius or higher for at least two consecutive days is expected to have a perceived temperature of 38 degrees or higher, or an actual temperature of 39 degrees or higher, for at least one more day.

Heat at that level carries a high risk of heat-related illness, so residents in the affected areas are advised to avoid outdoor activities, particularly between 2 p.m. and 5 p.m. when temperatures peak, and to rest in a shaded area or shelter. Water or sports drinks are recommended over caffeinated beverages or alcohol.

Sunday marked the warning's first activation since it was introduced last month to alert the public of extreme heat, which the previous heat wave warning could not adequately convey.

Under the earlier two-tier system, a heat wave advisory is issued when the perceived temperature is expected to reach 33 degrees or higher for two or more consecutive days, and a heat wave warning when it is expected to reach 35 degrees or higher for the same duration. The new "emergency" warning reflects how much more frequent and severe heat waves have become.

In Gyeongsan, the temperature climbed to 37.9 degrees at around 3 p.m. Saturday, reaching 39.9 degrees in the city's Hayang-eup. In Pohang, the temperature in Gigye township hit 37.2 degrees on Saturday.

Most other parts of the country have also had heat wave advisories or warnings issued since Saturday.

People cool off in the water at Ttukseom Hangang Park in Seongdong District, Seoul, Sunday, under a heat wave warning issued for the city. Korea Times photo by Choi Ju-yeon

Driving the heat are the North Pacific and Tibetan high-pressure systems, both bearing down on Korea. Southern parts of North Gyeongsang Province, including Gyeongsan and Pohang, are seeing particularly high temperatures due to the foehn effect, in which south winds blowing over the mountains grow hotter as they descend.

In the coming days, the perceived temperature is forecast to hover around 33 degrees in most areas, while reaching about 35 degrees in the greater Seoul area, Chungcheong region and southern provinces.

Rain is forecast for those regions from Monday to Wednesday, but the rain is unlikely to cool down the temperatures much. Following the emergency warning, the Korea Disease Control and Prevention Agency advised vulnerable groups, including children, older adults and those with cardiovascular disease, to take extra care of their health.

The relative risk of death rises to 1.16 times normal when temperatures reach the threshold for the emergency warning, according to the agency's analysis of data from 2016 to 2024.

The heat wave advisory system was overhauled with the introduction of the emergency warning, the first such change in 18 years.

Korea had an average of 19 days a year with a maximum temperature of 33 degrees or higher from 2021 to 2025, more than double the eight such days recorded in the 1970s.

Commuters use parasols and fans to beat the heat at Yeouido Transfer Center in Yeongdeungpo District, Seoul, Sunday, under a heat wave warning issued for the city. Yonhap