The warning is issued if the temperature is expected to remain above 33 degrees Celsius.
On Wednesday, the temperature in Seoul was 32.6 degrees Celsius as of 1 p.m., according to the Korea Meteorological Administration.
Seoul and a number of other regions nationwide have also experienced “tropical nights” since Wednesday, defined by nighttime lows above 25 degrees Celsius.
The agency also issued a warning in some other cities in Gyeonggi and Gangwon Provinces.
By Claire Lee(firstname.lastname@example.org)