South Korea heat wave to persist through next week, Daegu to hit 39°C
Synopsis
South Korea's heat wave is not just lingering — it is set to intensify. With the North Pacific High and Tibetan High locked simultaneously over the peninsula, the KMA warns of daytime highs up to 39°C in Daegu and 37°C in Seoul by 5 August. A wind shift around 4 August will push the worst heat westward, directly toward the Seoul metropolitan area.
Key Takeaways
The Korean Meteorological Administration (KMA) confirmed on 30 July that South Korea's heat wave will persist through at least 9 August .
Daytime temperatures will range from 33°C to 39°C between 3 and 9 August across the peninsula.
Daegu is forecast to record the highest temperatures at 38–39°C ; Seoul is expected to peak at 37°C on 5 August .
The simultaneous presence of the North Pacific High and Tibetan High is driving the sustained heat — and both systems are expected to strengthen, not weaken.
An easterly wind shift around 4 August will move the hottest conditions from the eastern to the western side of the Baekdudaegan range , affecting the Seoul metropolitan area .
South Korea is bracing for a prolonged heat wave that is set to continue well into next week, as the dominant pressure systems over the Korean Peninsula show no signs of weakening, the Korean Meteorological Administration (KMA) said on Thursday, 30 July. The combination of stagnant high-pressure systems and a sustained inflow of hot, humid air from the south is expected to keep temperatures dangerously elevated through at least 9 August.
Why the Heat Is Not Letting Up
The KMA attributed the persistent heat to a rare simultaneous presence of two powerful high-pressure systems — the North Pacific High and the Tibetan High — sitting over the peninsula at the same time. Far from dissipating, these systems are expected to intensify further as the air continues to heat up and expand.
The stagnant pressure pattern, combined with uninterrupted inflow of warm, moist air from the south, is maintaining clear skies and amplifying solar heating — a feedback loop that is pushing temperatures well above seasonal averages.
Temperature Forecast: What the Numbers Show
According to the KMA, morning temperatures from 3 to 9 August will range between 24°C and 27°C, while daytime highs are forecast between 33°C and 39°C. Daytime temperatures are expected to exceed historical averages from 2 to 9 August.
City-specific forecasts paint a stark picture. Seoul's daytime high is projected to reach 37°C on 5 August. The port city of Busan is expected to record 34°C on the same day. The southeastern city of Daegu — historically one of South Korea's hottest urban centres — is forecast to see daytime highs of 38°C to 39°C through next week.
Hotspot Shifts from East to West
One notable development is a geographic shift in the heat's epicentre. The KMA noted that the hottest region will move from the eastern side to the western side of the Baekdudaegan mountain range — the spine of mountains running north to south across the Korean Peninsula — as wind direction shifts to an easterly flow around 4 August.
This shift will bring intensified heat to the Seoul metropolitan area and other western regions that had previously seen relatively lower temperatures compared to the east. The Seoul metropolitan area is home to roughly half of South Korea's population of approximately 51 million, making the forecast particularly significant from a public health standpoint.
Health and Public Safety Concerns
Prolonged heat waves of this intensity carry serious risks, particularly for the elderly, outdoor workers, and those without access to cooling. South Korean authorities have historically activated heat emergency protocols — including cooling centres and restrictions on outdoor labour — during such events. This comes amid a broader pattern of increasingly severe summer heat across East Asia, with climate scientists linking more frequent and intense heat waves to long-term warming trends.
With no significant weather change on the horizon, authorities and residents across the peninsula will be closely watching the KMA's daily updates as the heat wave enters what could be its most intense phase next week.
Point of View
The public health calculus changes sharply. South Korea has invested in urban heat mitigation, but the true stress test is a sustained multi-week event, not a brief spike — and that is precisely what the KMA is now forecasting.
NationPress
30 Jul 2026
Frequently Asked Questions
How long will South Korea's heat wave last?
According to the KMA, the heat wave is expected to persist through at least 9 August 2025. The pressure systems driving the heat are forecast to strengthen rather than weaken in the coming days.
Which cities in South Korea will be most affected by the heat?
Daegu in the southeast is forecast to see the highest temperatures, ranging from 38°C to 39°C next week. Seoul is expected to hit a daytime high of 37°C on 5 August, while Busan is forecast at 34°C on the same day.
Why is South Korea experiencing such an intense heat wave?
The KMA attributes the extreme heat to the simultaneous presence of the North Pacific High and the Tibetan High over the Korean Peninsula. These stagnant pressure systems, combined with hot and humid air flowing in from the south, are maintaining clear skies and intensifying solar heating.
What is the Baekdudaegan mountain range and why does it matter for the heat wave?
The Baekdudaegan is the main mountain range running north to south through the Korean Peninsula. It influences regional temperature patterns by separating eastern and western climate zones. The KMA says the heat epicentre will shift from the eastern to the western side of this range around 4 August, bringing more intense heat to the Seoul metropolitan area.
What temperature range is forecast for South Korea in early August?
Morning temperatures are expected to range from 24°C to 27°C, while daytime highs will be between 33°C and 39°C from 3 to 9 August, according to the KMA.
