Typhoon Khanun reached waters 70 km south of South Korea's southern coast early Monday morning on its way to land, according to the Korea Meteorological Administration (KMA).
About 450 flights were grounded across the country Thursday due to the impact of Typhoon Khanun.
According to airport authorities, out of the 2,138 flights planned for the day, 452 had been suspended.
The count of affected operations is predicted to rise as the typhoon advances, according to airport officials.
The KMA indicated that the typhoon is expected to make landfall on the southern coast during the next few hours.
All regions across South Korea, except for the northern parts of the central region, were under typhoon warnings until this morning.
With the country under the influence of the typhoon, the eastern coast regions continued to receive rain at a rate of 30 mm per hour, while the southern regions were suffering from winds of up to 25 meters per second.
Jeju Island, located in southern South Korea, witnessed precipitation, with an average of 275.5 mm of rain.