Korea braces for return of heat as southern rains taper off

After heavy rains that battered Korea's southern regions subsided on Tuesday, sweltering heat is now expected to make its return — with a vengeance. The greater Seoul area is expected to see apparent temperatures climb as high as 36 degrees Celsius (96.8 degrees Fahrenheit) during the day.

“Rain is expected in parts of Jeju through [Tuesday] afternoon, while showers accompanied by gusty winds, thunder and lightning are expected across much of the country,” the Korea Meteorological Administration (KMA) said. “Sweltering heat is expected, particularly in the Seoul metropolitan area, Chungcheong and southern regions, where maximum apparent temperatures will hover around 33 degrees Celsius.”

All heavy rain advisories and warnings for southern regions have been lifted, with a heavy rain advisory remaining in effect only for some parts of Jeju.

As temperatures rise, more areas are once again coming under heat wave advisories.

A heat wave advisory went into effect across most of Seoul at 11 a.m. Tuesday, excluding the northwestern districts. Seoul's daytime high has been forecast to reach 32 degrees Celsius, with the apparent temperature reaching 33 degrees Celsius.

Heat wave advisories have also been issued in other parts of the country, including Daejeon and Daegu.

High humidity is expected to make the heat increasingly oppressive. On Thursday, the apparent temperature is forecast to reach 35 degrees Celsius in Seoul and as high as 36 degrees Celsius in parts of Gyeonggi.

Daytime showers caused by atmospheric instability may briefly ease the heat, but the muggy weather could feel even harsher once the rain stops.

“Temperatures may temporarily fall in areas that receive rain or showers, but they will rise again afterward while humidity remains high, and more areas may come under heat wave advisories and warnings,” a KMA official said.

Tropical nights — a phenomenon in which the mercury stays at or above 25 degrees Celsius overnight — are also expected to return in force. Daily low temperatures in some areas, including Jeju and Cheongju in North Chungcheong, stayed above 25 degrees Celsius on Tuesday.

Seoul also endured a sweltering night, with its lowest apparent temperature reaching 26.6 degrees Celsius. For the time being, the apparent temperature is not expected to fall below 27 degrees Celsius overnight.

“Temperatures in some urban and coastal areas will not cool sufficiently overnight and will remain at or above 25 degrees Celsius and bring tropical night conditions,” the KMA said.

BY CHON KWON-PIL [lee.soojung1@joongang.co.kr]