Korea experienced blistering heat on Wednesday as the mercury rose to 35-38 degrees Celsius nationwide except for the eastern part of Gangwon Province and some coastal areas. Heat warnings were issued in most parts of the country.

Of 92 weather observation posts across the country, 23 saw their highest temperatures for August. The Korea Meteorological Administration advised the elderly and frail to stay indoors on Thursday as sweltering heat continues.

Typhoon Damrey is being blamed for the extremely hot weather. Advancing northwestward from southern Japan to Jeju Island, it boosted easterly winds created by a North Pacific high-pressure system, resulting in heat waves in western Korea, the KMA said.

Scorching heat will continue until late August. "Generally, the nation sees its highest temperatures in early August before they begin to fall slightly in mid-August to the levels similar to those of late July, and this summer will see a similar pattern," the KMA said.

Korea has been affected by parching heat for the last 10 days, and that could continue at least until mid-August. Seoul experienced the fifth consecutive so-called tropical night when the mercury stayed above 25 degrees.

Meanwhile, Jeju and the southern coastal areas will come under the influence of the typhoon on Thursday and Friday when they will experience strong winds with over 150 mm heavy rainfall, the KMA said.

The typhoon was forecast to reach the sea 110 km southwest of Jeju on Thursday morning before advancing toward China's Qingdao and inland areas. The KMA forecast gusts with speeds of up to 15-25 m per second bringing downpours of over 30 mm per hour in some parts of Jeju and the southern coastal areas on Thursday. But other regions will not be directly affected by the typhoon.