South Korea Treats Record Heatwave as National Disaster After 19 Deaths

Deadly Heat Prompts a National Response

South Korea is treating an extreme heatwave as a national disaster after temperatures reached 42.5 degrees Celsius in Yangsan and authorities recorded 19 deaths from heat related causes. President Lee Jae Myung ordered a nationwide response as the crisis brought the first severe heatwave warning covering all of Seoul, disrupted outdoor activities and increased pressure on electricity supplies.

At a cabinet meeting on Tuesday, Lee directed officials to protect vulnerable residents, inspect power grids as demand for air conditioning surged and redesign the disaster response framework. He warned that abnormal weather patterns make prolonged periods of extreme conditions more probable.

The Korea Disease Control and Prevention Agency reported that 13 of the 19 people who died were aged 80 or older. Since May 15, at least 2,025 people nationwide have received treatment for illnesses related to heat. The figures put elderly residents at the centre of the emergency response, alongside people working outdoors and those living in cramped homes without air conditioning.

As of August 5, 2026, the response extended from national instructions to neighbourhood checks, cooling shelters and water spraying on city roads. The heat also affected neighbouring countries, with thousands requiring hospital treatment in Japan and nationwide heat advisories remaining in place in North Korea.

Yangsan Reaches 42.5 Degrees Celsius

Yangsan, in southeastern South Korea, reached 42.5 degrees Celsius on Sunday, the highest temperature in 122 years of observations by the Korea Meteorological Administration. Goryeong recorded 41.2 degrees Celsius, while a district of Seoul climbed to 39 degrees Celsius.

The readings show how far the heat spread beyond a single location. Yangsan was 1.3 degrees hotter than Goryeong and 3.5 degrees hotter than the Seoul district, based on the reported temperatures. All three places faced conditions that prompted concern about outdoor work and daily activities.

Forecasters linked the extreme temperatures to overlapping high pressure systems and the foehn effect. The latter describes air warming as it descends mountain ranges. Together, these weather conditions helped drive temperatures to levels unseen in more than a century of observations.

Seoul Expands Its Highest Heat Alert

The Korea Meteorological Administration issued its first severe heatwave warning for all of Seoul on Tuesday. The warning had initially covered southern and western districts before authorities expanded the highest alert level across the capital on Tuesday morning.

The alert is triggered when perceived temperatures exceed 38 degrees Celsius or actual maximum temperatures surpass 39 degrees Celsius. Perceived temperature describes how hot conditions feel, while the actual temperature is the measured reading. The warning therefore accounts for the heat people experience as well as the thermometer reading.

Residents were advised to halt outdoor activities, including farming, sports and construction work. The highest alert level requires the immediate suspension of outdoor work that is not essential. Two professional baseball games scheduled in Seoul and Gwangju were also cancelled because of safety concerns.

The main developments unfolded over several dates:

• May 15: The reporting period began for the nationwide tally of at least 2,025 people treated for illnesses related to heat.
• Sunday: Yangsan reached 42.5 degrees Celsius, and two elderly men died while working outdoors.
• Tuesday morning: The highest heat warning was expanded across all of Seoul.
• Tuesday: President Lee directed authorities at a cabinet meeting to treat the heatwave as a national disaster.

Elderly Residents Bear Much of the Loss

The Korea Disease Control and Prevention Agency's death toll shows the heavy toll among the oldest residents. People aged 80 or older accounted for 13 of the 19 deaths, or roughly two thirds of the total.

Two elderly men died on Sunday while working outdoors. One was working in a greenhouse near Seoul, and the other was in Busan. Their deaths brought attention to both outdoor workplaces and enclosed spaces exposed to intense heat.

Lee called for stricter oversight of those workplaces and enforcement of workers' rights to pause operations during extreme heat. His instructions placed responsibility on authorities to check working conditions as well as issue warnings.

The national response also focused on elderly people living alone and residents with chronic illnesses. In Seoul, nurses were deployed to check on 63,000 residents considered at risk, making direct contact with vulnerable people a central part of the city's emergency measures.

Cramped Homes Offer Little Relief

Residents of jjokbang villages, areas of small single room housing without air conditioning, described heat unlike anything they had experienced before. The housing conditions leave some residents with little relief inside their own rooms.

Cho Sang-yeon, who has lived for nearly 20 years in western Seoul's Yeongdeungpo district, said the current heat exceeded anything he had felt previously. His experience reflected the hardship facing residents who cannot cool their living spaces.

Some residents moved to temporary government shelters with cooling. Firefighters sprayed streets and monitored homeless people, while support measures also targeted people living in cramped housing and elderly residents living alone.

Lee's instructions connected these living conditions with the wider disaster response. Protecting vulnerable groups meant addressing where people could find cooling, while enforcing work pauses addressed exposure during the working day.

Road Spraying and Drones Join the Response

Seoul officials held emergency meetings as the warning expanded across the city. Alongside visits by nurses, the capital deployed a fleet of 200 trucks to spray water along nearly 2,000 kilometres of roads, with spraying carried out up to six times daily.

Mist systems operated continuously. These measures formed part of the city's effort to respond to heat across streets and public spaces while shelters provided cooling for residents who needed somewhere else to stay.

North Gyeongsang province used drones fitted with loudspeakers and thermal cameras to monitor popular outdoor sites and issue warnings. The equipment allowed authorities to combine monitoring with messages to people spending time outside.

The city and provincial measures worked alongside the restrictions on outdoor activities. Road spraying, personal checks and warnings addressed different parts of the same emergency, from crowded public places to residents who might be alone at home.

Japan and North Korea Also Face Extreme Heat

Japan recorded nearly 18,600 people requiring hospital treatment for heatstroke between July 20 and 26. Of those, 45 arrived deceased. The figures show the scale of the health emergency elsewhere in East Asia during the regional heatwave.

Three lions at Tokyo's Tama Zoological Park died from suspected heatstroke despite countermeasures. A zoo spokeswoman pointed to high humidity as a difference between Japanese summers and the drier conditions in Africa.

North Korea maintained nationwide heat advisories. Water parks in Pyongyang attracted crowds as the heat continued, while South Korea's response centred on severe alerts, work restrictions and support for vulnerable residents.

The emergencies across the region shared a common concern: prolonged heat was affecting health and daily life. Japan's hospital figures, South Korea's deaths and North Korea's advisories each showed a different part of that regional picture.

Why the Heat Is Lasting Longer

The Korea Meteorological Administration attributed the prolonged heat to an earlier and stronger North Pacific high pressure system, together with warmer sea surface temperatures. These conditions sustain humidity and produce more frequent tropical nights, when heat continues into the night.

The overlapping high pressure systems and the warming of air descending mountains explain the immediate extreme conditions. The earlier arrival and greater strength of the North Pacific system help explain why the heat has persisted.

South Korea's heatwaves now arrive earlier and last longer than in previous decades. The annual number of days with temperatures reaching at least 33 degrees Celsius has more than doubled over the past five years compared with the 1970s.

Scientists attribute the increasing frequency and intensity of heatwaves to climate change driven by human activity. The United Nations weather agency also warned of a strengthening El Nino, a climate pattern likely to raise global temperatures and alter rainfall patterns. These developments form the wider climate setting for the extreme weather.

Electricity Supplies and the Storm Outlook

Authorities were monitoring electricity grids as demand for air conditioning reached new peaks. Lee ordered inspections to prevent outages that could endanger residents during the hottest hours, when access to cooling becomes especially important.

The pressure on electricity supplies connected the weather emergency with infrastructure planning. Lee's call to redesign the disaster response framework came alongside his warning that abnormal weather patterns make long periods of extreme conditions more probable.

Typhoon Dolphin was approaching from the east, adding uncertainty to the immediate outlook. Depending on its track, the storm could increase humidity or bring temporary relief from the heat.

Forecasters expected Dolphin to weaken before landfall as a category one or two system. Its effect on the heat remained uncertain because that depended on where it travelled. Meanwhile, authorities continued checks on power supplies, restrictions on outdoor activities and support for residents most exposed to the heat.

Key Points

• President Lee Jae Myung ordered authorities to treat the heatwave as a national disaster and redesign the response framework.
• Yangsan reached 42.5 degrees Celsius, the highest temperature in 122 years of Korea Meteorological Administration observations.
• Authorities recorded 19 deaths from heat related causes, including 13 people aged 80 or older, and at least 2,025 people treated since May 15.
• Seoul received its first severe heatwave warning covering the entire capital, with restrictions on outdoor activities.
• Seoul deployed nurses to check 63,000 vulnerable residents and 200 trucks to spray nearly 2,000 kilometres of roads.
• Japan recorded nearly 18,600 people requiring hospital treatment for heatstroke from July 20 to 26, with 45 arriving deceased.
• Three lions died from suspected heatstroke at Tokyo's Tama Zoological Park, while North Korea maintained nationwide heat advisories.
• Authorities monitored electricity supplies as Typhoon Dolphin approached, with its effect on the heat dependent on its track.