May 2023 in South Korea had an average temperature of 17.9C which is 0.6C above the 1991-2020 normal. (left map)
Spring was the warmest on records with an average temperature of 13.5C and +1.6C above average (right map).
Maps are courtesy of KMA.
https://nitter.moomoo.me/extremetemps/status/1664965152003829761#m