Even on the 7th, the seasonal onset of autumn (Ipchu), extreme heat will continue across most of the country, with highs reaching 39 degrees. However, starting this weekend, a change in the pressure pattern will bring a slight drop in temperatures, easing the intensity of the heat. Still, higher-than-usual temperatures are expected to continue into next week.
According to the Korea Meteorological Administration on the 6th, through the 7th, high pressure overlapping from the lower to upper atmosphere over the Korean Peninsula will combine with strong sunshine and hot air, likely pushing the heat wave to its peak.
On the 7th, morning lows are forecast at 22–27 degrees, with daytime highs of 31–39 degrees. By major city, daytime highs are expected to reach 39 degrees in Seoul; 38 in Incheon and Gwangju; 37 in Daejeon and Daegu; 35 in Busan; and 34 in Ulsan.
From the weekend, as the center of high pressure shifts to the northwest of Korea, clouds will move into the upper atmosphere and easterly winds will blow in. Accordingly, on Saturday the 8th, daytime highs are expected at 27–36 degrees, and on Sunday the 9th, 26–36 degrees, a slight decrease.
However, that does not mean the heat wave is over. Considering that typical daytime highs for this time of year are 29–33 degrees, the Korea Meteorological Administration expects weekend and next-week temperatures to remain above average. During the week of the 10th–16th, morning temperatures are expected at 22–26 degrees and daytime temperatures at 28–36 degrees, higher than normal.
Over the weekend, due to easterly winds, heavy rain will fall mainly along the east coast and in Jeju. As the easterly winds cross the Taebaek Mountains, rain clouds will intensify, with 30–80 millimeters forecast for the Gangwon east coast and mountainous areas, and more than 120 millimeters in places. The northern east coast and northeastern mountains of North Gyeongsang are expected to see 20–60 millimeters; the southern east coast of North Gyeongsang, 5–40 millimeters; and Jeju's mountains and mid-mountain areas, 5–30 millimeters.
In the Gangwon region, there is a possibility of very heavy rain of 30–50 millimeters per hour between early morning and late morning on the 8th, requiring special caution for facility management and safety accidents. The rain is expected to continue through the 9th, and in Jeju through the morning of the 10th.
The Korea Meteorological Administration said temperature volatility in the latter half of next week could increase depending on how the East Asian pressure pattern reorganizes after Typhoon No. 13 "Dolphin" makes landfall south of Shanghai, China, around the 10th. If cold air from the north moves in, the heat could ease, but if the North Pacific High and the Tibetan High once again cover the Korean Peninsula, the possibility of a return to extreme heat cannot be ruled out.