South Korea's inland regions are under heatwave and tropical-night warnings following a period of heavy rainfall [1, 2].
These rapid shifts between extreme precipitation and intense heat stress public infrastructure and health systems. The volatility is driven by a north-Pacific high-pressure system that is pushing hot, humid air across the peninsula [1, 2].
Weather alerts have expanded across the interior as rain subsided. In Seoul, a heatwave advisory was extended to cover the entire city, while Ulsan was placed under a more severe heatwave warning [1]. Apparent temperatures in some areas have reached around 35 °C [1].
Reporter Jung Hye-yoon said the return of the heatwave immediately after the southern extreme rains is due to the expansion of the north-Pacific high-pressure system [1]. This system creates a sharp temperature gradient at its edge, which can trigger the formation of strong rain clouds [1, 2].
Forecasters expect another spell of rain later this week. This anticipated precipitation is caused by the strong temperature contrasts between the humid air mass and cooler atmospheric conditions [1, 2].
While the current heat is not described as reaching the extreme levels seen earlier this month, the transition from flooding to heatwaves has become a recurring pattern [1]. Local authorities continue to monitor the inland regions as the weather remains unstable, a result of the competing pressure systems [1, 2].
“Apparent temperatures in some areas have reached around 35 °C.”
The rapid oscillation between 'extreme rain' and 'extreme heat' indicates a heightened atmospheric instability in the region. This volatility, driven by the expansion of the north-Pacific high-pressure system, suggests that South Korea is experiencing more polarized weather patterns where the transition between disaster types occurs with little recovery time for urban centers.
