Geoje city on the southern coast of South Korea received approximately 960 mm of rain over three days [1].
The extreme volume of water represents a significant meteorological event for the Gyeongsangnam-do region. Such concentrated rainfall can overwhelm urban drainage systems and increase the risk of landslides in coastal terrain.
Kim Min-kyung, a meteorologist, said the total rainfall nearly reached 1,000 mm [1]. This amount is equivalent to about half of Geoje's annual average rainfall, which is 1,930 mm [1]. The three-day deluge also exceeds the city's average summer rainfall of 935 mm [1].
A single day during the period recorded more than 600 mm of rain [1]. This specific daily total ranks as the third-highest daily rainfall amount in the history of Geoje city [1].
Weather analysts said a specific atmospheric condition caused the downpour. An easterly wind blocked the movement of rain clouds, which concentrated the precipitation over the southern coast [1].
The event occurred without the presence of a typhoon, distinguishing it from typical seasonal storm patterns in the region [1].
“Approximately 960 mm of rain fell in three days.”
The occurrence of record-breaking rainfall without a typhoon suggests that localized atmospheric blocking—such as the easterly winds noted in this case—can produce weather extremes equal to or greater than major tropical storms. This highlights a vulnerability for South Korea's southern coastal cities to non-typhoon precipitation events that can deliver a significant percentage of yearly rainfall in a matter of days.
