Heavy rain may fall under the influence of a stationary front from the night of Aug. 29 through the morning of Aug. 31. More than 200 mm of rain is forecast for Daejeon, Sejong, and Chungnam from Aug. 30 to 31, making it important to check weekend travel routes and conditions around nearby facilities in advance.
When Chungnam Could See the Heaviest Rain
In Daejeon, Sejong, and Chungnam, intense rain exceeding 50 mm per hour is expected from 3 a.m. to 9 a.m. on Aug. 30 and from 6 a.m. to noon on Aug. 31. Parts of Chungcheong and Honam could also receive more than 50 mm of rain per hour on Aug. 30.
This forecast should be assessed not only by daily accumulated rainfall but also by the periods when rain may be concentrated within a short time.
Heavy rain can be concentrated in a narrow area, causing significant differences in rainfall even between nearby locations. Actual rainfall intensity and accumulation may therefore vary within the same province or metropolitan area.
How the Forecast Differs by Region
| Region | Rainfall outlook for Aug. 30–31 |
|---|---|
| Daejeon, Sejong, and Chungnam | More than 200 mm possible; some periods may exceed 50 mm per hour |
| Chungbuk and Jeonbuk | More than 150 mm possible |
| Gwangju, Jeonnam, and southern Gyeonggi | More than 100 mm possible |
| Inland and mountainous Gangwon | 5–30 mm on Aug. 30; expected to ease from the morning |
| Gangwon east coast | 5–10 mm on Aug. 30; expected to ease from the morning |
In areas expecting torrential rain, including Chungnam, water levels in underpasses and valleys can rise quickly. Gusty winds, thunder, and lightning may also accompany the rain, so people in these areas should check the latest weather conditions and nearby hazards.
The ‘Up to 80 mm in Gangwon’ Figure Has Not Been Confirmed
A related trending search term included the phrase “up to 80 mm in Gangwon on Sunday,” but the figure could not be confirmed in the latest independent sources reviewed in the research package. The forecasts that were confirmed specify 5–30 mm for inland and mountainous Gangwon and 5–10 mm for the Gangwon east coast, with rain expected to ease from the morning of Aug. 30.
Forecasts can change depending on the time and location. Before publication, check the Korea Meteorological Administration’s Weather Nuri service, weather advisories, and the latest radar imagery again.
Confirmed Sources
- YTN, “[Weather] Beware of Extreme Rain Overnight… More Than 200 mm Possible in Chungcheong,” checked Aug. 29, 2026, at 09:15 UTC: https://www.ytn.co.kr/_ln/0108_202608291617557888
- SBS News, “Torrential Rain from Early Tomorrow… More Than 200 mm Possible in Chungnam,” checked Aug. 29, 2026, at 09:15 UTC: https://news.sbs.co.kr/news/endPage.do?cooper=SBSNEWSEND&news_id=N1008727838&oaid=N1000210353&plink=TOP
- Yonhap News Agency, “Rain Nationwide on the Last Weekend of August… More Than 50 mm per Hour in Chungcheong and Honam on Sunday,” checked Aug. 29, 2026, at 09:15 UTC: https://www.yna.co.kr/view/AKR20260828152600530