Seoul braces for scorching 36-degree heat wave this week

A pedestrian cools off with a handheld fan on a street in central Seoul, Monday, as the Korea Meteorological Administration issued the first heat wave warning of the summer for the city. Newsis

Korea is bracing for a relentless heat wave this week, with meteorologists warning that the worst is yet to come for Seoul and the western regions.

The Korea Meteorological Administration (KMA) upgraded heat wave advisories to warnings for the capital and much of the west on Monday, with temperatures in Seoul expected to reach 36 degrees Celsius throughout the week.

Heat wave warnings covered 122 of the nation’s 183 weather zones. Another 55 areas remained under advisories. A heat wave advisory is issued when temperatures are expected to reach 33 degrees Celsius or higher for more than two days. A heat wave warning is issued when highs of 35 degrees or above are forecast to persist for over two days, with the potential to cause serious health risks and disruptions across affected regions.

As the mercury soared across the Korean Peninsula, the capital found itself particularly vulnerable to the early onslaught of summer's fury.

For Seoul, this marks the first heat wave warning of the season, a striking 18 days earlier than last year's record-setting heat.

Forecasts show that daytime highs in Seoul could hover around 36 degrees on both Tuesday and Wednesday, which, if realized, could break the capital’s all-time early-July record of 36.8 degrees, set on July 9, 1939. The KMA warns that the combination of high humidity and intense sunlight will make weather conditions even more oppressive.

In Miryang, South Gyeongsang Province, the temperature soared to a scorching 39.2 degrees Celsius at 1:45 p.m. Monday — nearly 10.2 degrees above the seasonal average and the highest early July temperature recorded in the city since meteorological observations began in 1973.

Last week, temperatures soared to 38.7 degrees Celsius on the eastern slopes of the Baekdu Daegan mountain range, including in Gangneung, Gangwon Province. Now, the heat is shifting westward. Meteorologists attribute the change to shifting wind patterns, with easterly breezes expected to cool the east while intensifying the heat in Seoul and surrounding areas.

Heat haze rises from an asphalt road in Jeju, as the island's daytime high exceeded 32 degrees Celsius, Monday. Newsis

The persistent heat has already led to a spike in heat-related illnesses across the country.

According to the Korea Disease Control and Prevention Agency, 875 cases of heat-related illness and seven deaths were reported nationwide between May 15 and July 6 — over 350 more cases than during the same period last year.

The number of tropical nights — when overnight lows stay above 25 degrees Celsius — is rising. Seoul has recorded eight consecutive tropical nights, while coastal cities like Gangneung and the southern resort island of Jeju have endured a week of stifling nighttime heat.

In response to the escalating threat, Seoul Metropolitan Government has moved to emergency footing, raising the heat wave crisis alert from “caution” to “alert.”

Prime Minister Kim Min-seok began his first day in office by visiting a construction site to inspect heat safety protocols, marking his inaugural official schedule. He emphasized the need for both public and private sectors to adopt standardized guidelines to protect vulnerable workers.

Prime Minister Kim Min-seok, left, visits a construction site in Sejong, Monday, to inspect heat safety protocols. Yonhap

“Heat waves are a social disaster that hit the socially and economically vulnerable the hardest,” he said, calling for close cooperation between government and parliament to minimize harm.

Meteorologists expect the heat wave to persist through the week, with only a slight reprieve possible after the weekend. Cooler northern air is forecast to push southward by Saturday, potentially bringing rain to the capital and central regions by the middle of next week.

However, the KMA has yet to declare the end of the rainy season for central Korea, citing likelihood of further unsettled weather.