Seoul is preparing for its first-ever "severe heatwave warning" today, Tuesday 4 August 2026. This comes as South Korea experiences a deadly heatwave, which saw the south-eastern city of Yangsan record an all-time national high of 42.5C on Sunday afternoon. This temperature is the highest measured in 122 years of weather observations.
The heat is now moving westwards towards the capital, which has a population of over 9 million. Seoul is forecast to reach 38C today, with three subsequent days expected to hit 37C.
Since May, South Korea has recorded 16 fatalities linked to heat and more than 2,000 people have been treated for heat-related illnesses, according to the Korea Disease Control and Prevention Agency. President Lee Jae Myung has urged officials to protect citizens and inspect power systems due to surging air conditioning demand.
Seoul authorities held an emergency meeting on Monday and have launched initiatives to mitigate health risks. Nurses are checking on up to 63,000 vulnerable residents, including the elderly and those with disabilities or chronic illnesses. Additionally, 200 trucks are spraying nearly 2,000km of roads with water up to six times a day in problematic areas to reduce urban heat.
The Korea Meteorological Administration (KMA) attributes the heatwave to overlapping high-pressure systems over the Korean peninsula, combined with strong, direct sunlight. The KMA also noted that Typhoon Dolphin could either worsen conditions by increasing humidity if it moves towards eastern China, or temporarily ease the heat with stronger winds, cloud cover, and rain if it tracks closer to the south of the peninsula.