South Korea Experiences Early Summer Heat as Seoul Air Quality Drops
Unseasonably warm temperatures swept across South Korea on Wednesday, April 15, 2026, with many regions experiencing weather more characteristic of early summer than mid-spring. The persistence of unseasonably early heat has seen daytime highs climb 2 to 5 degrees Celsius above the historical average.
The capital city felt the brunt of the warmth, with Seoul reaching a high of 26 degrees Celsius. Chuncheon also hit 26 degrees, while Daejeon, Gwangju, and Daegu recorded highs of 25 degrees. Other regional temperatures included 24 degrees in Chungju and Jeonju, 21 degrees in Busan, 19 degrees in Jeju, and 17 degrees in Gangneung.
While the afternoons were warm, the region faced significant temperature fluctuations inland. Morning lows ranged between 6 and 13 degrees Celsius, creating a sharp diurnal temperature gap of approximately 15 degrees. These erratic shifts often pose challenges for public health, particularly for those susceptible to respiratory issues during sudden weather transitions.
Environmental conditions were more concerning in the metropolitan area. Seoul air quality remained poor, with fine dust levels classified as “bad” across Seoul, Incheon, and southern Gyeonggi province. In contrast, air quality in other parts of the country was rated as “good” to “moderate.” The combination of high heat and poor air quality in the capital underscores the growing volatility of spring weather patterns in the region.
Weather conditions varied by region, with most of the country remaining partly cloudy. Those in the warm spring weather in Gwangju and South Jeolla Province saw skies clear from the morning. Jeju experienced light morning showers with total rainfall under 5mm, while heavy fog reduced visibility to less than 1km in the Gangwon mountains and along the east coast through Wednesday morning.
