166mm 'Deluge' Hits Seoul but More Rain Coming... In the South, "Perceived Temperature 33°C, Use Your Umbrella" [Weather]

Umbrellas for Seoul Metropolitan Area, Parasols for the South

Simultaneous Forecasts of Rain and Heat Wave

Due to the influence of a stationary front, rain is expected across most regions nationwide on July 18. In the Seoul metropolitan area, there is a possibility of heavy downpours, while in the southern regions, rainy season showers are forecast along with sweltering heat, with apparent temperatures around 33 degrees Celsius. As a result, some regions may experience both rain and heat waves at the same time.

A scene of the Dongbu Expressway in Seoul on the 18th, which experienced heavy rainfall. Photo by Yonhap News

On July 18, Seoul saw very heavy rainfall with around 50 mm per hour concentrated in the southwest and northwest districts, prompting the issuance of a heavy rain warning. The total accumulated precipitation has reached up to 166.0 mm.

In particular, flood alerts were issued for Gangseo-gu, Eunpyeong-gu, and Mapo-gu. A flood alert is announced when rainfall reaches 50 mm in an hour or 90 mm in three hours. Additionally, flood advisories were issued for Mapo-gu and Yangcheon-gu. Such advisories are issued when 20 mm of rain falls in 15 minutes or 55 mm falls within one hour.

Fortunately, as the heavy rain clouds moved rapidly eastward and weakened in intensity, the heavy rain warnings for Seoul were lifted as of 7:30 a.m. that day.

The entire section of the Dongbu Expressway in Seoul has been fully closed on the 18th due to heavy rain. Yonhap News

However, an additional 30~80 mm of rain is forecast to fall through July 19. During the afternoon of the 18th and early morning of the 19th, there is the possibility of strong downpours at a rate of 20~30 mm per hour.

In Busan and Gyeongnam, daytime highs will remain between 29 and 32 degrees Celsius, while rain driven by the stationary front will keep the weather hot and humid. At 11 a.m., heat wave advisories were issued for western, central, and eastern Busan. These advisories are announced if the maximum apparent temperature exceeds 33 degrees Celsius for two consecutive days or if severe heat damage is expected.

The rain will continue from early morning on the 18th until the night of the 19th, with expected rainfall of 20~60 mm.

Morning lows are similar to the previous day: 24 degrees Celsius in Geochang and Sancheong; 25 degrees in Busan, Miryang, Jinju, and Tongyeong; and 26 degrees in Changwon and Namhae. Daytime highs will be 29 in Busan and Tongyeong, 30 in Geochang, 31 in Changwon, Sancheong, and Namhae, and 32 in Miryang and Jinju, falling 1~5 degrees compared to the previous day.

In Gwangju and Jeonnam, the stationary front will bring rainy season showers accompanied by thunder and lightning. Due to the front and a low pressure system developing along it, rain accompanied by gusts and thunder and lightning is expected from the morning until late at night on the 19th. Forecast rainfall is 30~80 mm.

Citizens are taking a walk wearing sun hats along the Namcheon riverside in Gyeongsan, Gyeongbuk. Photo by Yonhap News

In the southeastern part of Jeonnam, the maximum apparent temperature will rise to around 33 degrees Celsius, making it very hot. As in Busan and Gyeongnam, the Korea Meteorological Administration issued heat wave advisories at 11 a.m. for 15 locations in Jeonnam, including Yeosu. The affected areas are Yeosu, Hwasun, Yeongam, Yeonggwang-gun (excluding Nakwol-myeon), Damyang, Jangseong, Boseong, Gangjin, Hampyeong, Gokseong, Gokseong-nambu, Gokseong-bukbu, Naju-dongnam, Muan (northern), Haenam (northern), and Gurye (plain). Heat wave advisories are already in place for Suncheon and Gwangyang.

Daytime highs on this day are forecast to be between 30 and 32 degrees Celsius. In the southeastern portion of Jeonnam, the maximum apparent temperature will rise to about 33 degrees, and elsewhere it will reach around 31 degrees, making it very hot overall.

Additionally, through July 20, gusts and thunder and lightning are expected over the southern and western seas, with sea fog also occurring in some areas. Ships navigating or operating in these waters are advised to take caution.

Currently, storm surge advisories are in effect for Yeongam, Mokpo, Muan, and Shinan (excluding Heuksan-myeon).

This content was produced with the assistance of AI translation services.