Rain is expected across most of South Korea on August 31. Rain in the southern regions and Jeju Island is expected to mostly stop at night, but the amount of rainfall and the duration of rain will vary by area. In particular, the cumulative forecast for August 31 through September 1 calls for heavy rain in the Chungcheong region, southern Gyeonggi, Chungbuk, northwestern Jeonbuk, and the southern inland and mountainous areas of Gangwon. Regional figures should be checked separately when planning commutes and travel.
Key Developments
The key feature of this rainfall forecast is the high cumulative rainfall expected around the Chungcheong region. Southern Gyeonggi is expected to receive 50–100 mm, with some areas forecast to receive more than 150 mm. Daejeon, Sejong, and Chungnam are forecast to receive 80–150 mm, with more than 250 mm possible along Chungnam’s west coast and more than 200 mm possible inland in Chungnam. Chungbuk is also expected to receive 50–150 mm, with some areas forecast to receive more than 200 mm.
Heavy rain is also expected in parts of Jeonbuk and Gangwon on August 31 alone. Jeonbuk is forecast to receive 20–80 mm, with more than 120 mm expected in northwestern Jeonbuk. Gangwon is forecast to receive 30–80 mm, with more than 120 mm expected in the southern inland and mountainous areas of the province.
Even with the same forecast of “rain nationwide,” the level of preparation needed may differ depending on the expected rainfall in each region.
Current Status
The latest confirmed forecast calls for rain across most of the country on August 31. However, the one-day forecast for August 31 and the cumulative forecast for August 31–September 1 use different time frames, so the figures should not be confused. The forecasts of more than 250 mm along Chungnam’s west coast and more than 200 mm inland in Chungnam and in Chungbuk are cumulative figures for two days. The forecast of more than 120 mm in northwestern Jeonbuk and the southern inland and mountainous areas of Gangwon applies to rainfall expected on August 31.
| Region | Expected rainfall |
|---|---|
| Southern Gyeonggi | 50–100 mm from August 31 to September 1; more than 150 mm in some areas |
| Daejeon, Sejong, and Chungnam | 80–150 mm; more than 250 mm possible along Chungnam’s west coast and more than 200 mm inland |
| Chungbuk | 50–150 mm; more than 200 mm in some areas |
| Jeonbuk | 20–80 mm on August 31; more than 120 mm in the northwest |
| Gangwon | 30–80 mm; more than 120 mm in the southern inland and mountainous areas |
Areas under active weather alerts may change depending on the announcement time, so it is difficult to describe the current status as fixed. Check the active alerts on the Korea Meteorological Administration’s comprehensive weather-alert page just before departure. In areas receiving rain, also watch for gusty winds and thunder and lightning. Swell conditions along the east coast should be checked as well.
Impact
If you are planning to commute or travel, first determine which region your destination belongs to and whether the rainfall figure you are checking is for one day or a cumulative period, rather than looking only at whether it will rain. Southern Gyeonggi and the Chungcheong region are areas with high cumulative rainfall forecasts for August 31–September 1, while northwestern Jeonbuk and the southern inland and mountainous areas of Gangwon are expected to receive heavy rain even on August 31 alone.
Rain in the southern regions and Jeju Island is expected to mostly stop at night, but conditions may feel different depending on when you travel because most of the country is expected to see rain that day. In areas where gusty winds and thunder and lightning are expected, do not assess conditions based on rainfall figures alone; check the latest weather information as well. If you are traveling to the east coast, check for possible swells separately from the rain forecast.
Next Checkpoint
The most important time to check conditions is just before departure. The Korea Meteorological Administration’s comprehensive alert page provides information on currently active alerts, including heavy-rain alerts. Its radar and lightning services show the latest precipitation bands and lightning distribution.
Before leaving, check the following in order:
- Check the latest forecast and regional rainfall figures for your destination.
- Check the currently active alerts again on the Korea Meteorological Administration’s comprehensive alert page.
- Check the precipitation bands and lightning distribution through the radar and lightning services.
- If you plan to visit the east coast, also check for possible swells.
Forecast figures may change depending on the time of issuance. Use the broad outlook—rain across most of the country on August 31 and the forecast of heavy rain in specific regions—as a guide, but base decisions about travel and preparations on the official alerts and real-time radar information available just before departure.