South Korea is experiencing a heatwave with temperatures around 33 °C [1] following a period of intense rainfall across the peninsula.
This rapid shift between weather extremes poses significant risks to public safety and infrastructure, as the country oscillates between flooding and extreme heat.
Recent storms caused severe disruptions in coastal regions. In Geoje, hourly rainfall reached 100 mm [2], prompting emergency services to dispatch rescue teams as requests for assistance surged, YTN news said.
Weather officials said the current heatwave is driven by the expansion of the North Pacific high-pressure system. This system, combined with a distant tropical low-pressure system, is acting as a heat pump that pulls warm, moist air northward [1].
This atmospheric setup creates sharp temperature gradients. These contrasts generate strong rain clouds, which are expected to bring another spell of precipitation later this week [1].
While inland areas including Seoul and Ulsan are currently feeling the heat, coastal regions are more likely to see the development of stronger rain clouds [3]. The volatility is characterized by a pattern where extreme heat immediately follows heavy rain, a cycle that is intensifying the environmental stress on urban centers.
Reporter Jung Hye-yoon of YTN said that hot air covered the city as soon as the rain clouds retreated [1].
“Hourly rainfall in Geoje reached 100 mm [2]”
The oscillation between high-pressure heat pumps and tropical moisture indicates an increase in weather volatility. When extreme temperature contrasts meet moist air, the resulting instability often leads to unpredictable and concentrated precipitation, increasing the likelihood of flash flooding in urban areas like Seoul.
