This spring in Korea ranked as the second-warmest on record, with temperatures rising so rapidly that many people pulled out short sleeves before they had finished storing away their winter padded jackets.
According to the "Spring 2026 Climate Characteristics" report released by the Korea Meteorological Administration (KMA) on Tuesday, the nationwide average temperature this spring (March to May) reached 13.3℃, the second-highest since the national weather observation network was expanded in 1973. The figure was 1.4℃ above the historical average of 11.9℃ and 0.8℃ higher than last year's 12.5℃. The all-time high was set in 2023 at 13.5℃.
May alone set a new record. Last month's nationwide average temperature reached 18.6℃, the highest since observations began, and surged to 19.7℃ in mid-May, breaking the record for the same period. The number of heatwave days in May stood at 0.5 days, the second-highest on record. Twenty-two locations including Wonju and Daegu saw early heat that broke daily maximum temperature records on May 17-18.
The pattern of recurring spring heat is also becoming clearer. Seven of the past 10 years rank among the top 10 warmest springs on record. The KMA analyzed that the warming trend in spring is becoming structurally entrenched.
High sea surface temperatures are cited as a key cause. The average sea surface temperature in waters around Korea this spring was 14.0℃, the second-highest in the past decade.
Inflows of warm currents such as the Tsushima Warm Current and the East Korea Warm Current continued more strongly than last year, and May's sea surface temperature was 2.0℃ higher than the 10-year average. In addition, a high-pressure ridge that developed over central Siberia stagnated over the Korean Peninsula for an extended period, increasing solar radiation and pushing up surface temperatures.
The hot spring is expected to be followed by an unusual summer as well. The KMA forecasts that this summer will be hotter than usual with higher precipitation. The North Pacific high-pressure system began strengthening early in April, and hot air is flowing into the Korean Peninsula on westerly winds.
"This spring was a season in which we could feel the recent warming trend," KMA Administrator Lee Mi-sun said. "As damage from heatwaves, tropical nights, and the monsoon season may occur in summer, we will closely monitor abnormal climate phenomena and respond preemptively."
