Seoul is expected to reach a daytime high of 31 °C on Thursday, May 14, marking the highest temperature recorded so far this year [3].
The sudden spike in temperature signals an early arrival of summer heat, bringing risks of high ozone levels and intense ultraviolet radiation across the region. This shift in weather patterns may impact public health and energy demand as the peninsula transitions out of spring.
The Korea Meteorological Administration said the heat is being driven by strong spring sunshine and atmospheric instability [5]. According to the agency, an easterly wind crossing over mountain ranges is becoming hot and dry, which will further elevate temperatures in western regions [2].
Morning temperatures on Thursday are expected to be 15 °C in Seoul and Busan [5], while Daejeon will start at 14 °C [6]. By the afternoon, Gwangju is forecasted to reach 28 °C [7], Daegu 26 °C [8], and Gangneung 20 °C [9]. Current temperatures in Seoul have already risen to 25.7 °C [1], which is approximately three °C higher than the same time on Wednesday [2].
While the north remains dry, the southern regions will face unstable conditions. The Korea Meteorological Administration said brief showers with rainfall between five and 20 mm [4] are forecasted for the Honam and western Gyeongnam provinces. These showers may be accompanied by lightning and sudden wind gusts [4].
Residents are advised to monitor ozone and UV indices, as the combination of clear skies and high solar radiation increases the risk of heat-related illness. The agency said that the atmospheric instability is a result of high solar radiation and specific wind patterns moving across the terrain [5].
“Seoul daytime high of 31 °C marks the highest temperature recorded so far this year.”
The arrival of 30 °C+ temperatures in mid-May suggests an accelerated seasonal transition for South Korea. This early heat, combined with high ozone and UV levels, places earlier-than-usual pressure on public health infrastructure and urban cooling systems, while the simultaneous convective showers in the south highlight the volatility of the current atmospheric transition.
