In the photo taken last August in Jung-gu, Seoul, citizens are seen hurrying to avoid the rain./Photo=Newsis.
From the 25th, which is the substitute holiday for Buddha’s Birthday, rain that started in Jeju and some other regions is expected to spread nationwide. Particularly, as heavy rain is forecasted mainly in the southern regions over the next few days, caution is advised to avoid safety accidents.
The Korea Meteorological Administration (KMA) stated in its regular briefing on the 25th, “The rain, which begins in Jeju, is expected to expand nationwide by the 26th.” They explained that “a low-pressure system from the south meeting with a high-pressure system is creating a lower-level jet stream, likely resulting in heavy rain alerts for regions like Jeju and the southern coast.” The rain is expected to mostly stop by the morning of the 27th, but some parts of the east coast may continue to experience rain during the day due to easterly winds.
According to the KMA, the expected accumulated rainfall from the 26th to the 27th is predicted to be: 30-100mm in the metropolitan area and the five islands of the West Sea; 30-80mm in Gangwon Province; and 30-80mm in Daejeon, Sejong, Chungnam, and Chungbuk.
Rain is expected to focus heavily in the southern regions. The cumulative expected rainfall for the southern regions from the 25th to the 27th is: 80-200mm near the coast of Jeonnam and around Jirisan; 50-100mm in Gwangju and inland Jeonnam; 30-80mm in Jeonbuk; 80-150mm in the Gyeongsang region; and 50-300mm in Jeju.
Specifically, heavy and strong rain is highly probable with hourly rainfall reaching 50-80mm in the mountainous areas of Jeju, 50mm near the southern coast and Jirisan, and 30-50mm in the coastlines of Jeonnam, Gyeongnam, and Jeju.
The KMA has warned that downpours can cause water levels in streams and rivers to suddenly rise, advising against camping and caution when using riverside trails or underground passages. They also recommended being prepared for potential damage like retaining wall collapses and soil erosion in areas with weak soil.
In addition to rain, strong winds have been forecasted. From the morning of the 26th, strong winds with gusts over 70 km/h (20 m/s) are expected, particularly around the southern coast of Gyeongnam. Other regions nationwide may experience gusts of 55 km/h (15 m/s).
There is also a possibility of gale warnings due to high waves ranging from 1.5 to 3 meters in the South Sea west of the peninsula and around Jeju waters, so vessels engaged in navigation and operations need to be cautious.
From the 28th to the 29th, after the rain has stopped, the weather is expected to be mostly cloudy but to clear up in the morning. Morning temperatures will range from 14 to 18 degrees Celsius, and the maximum daytime temperatures will rise to 27 to 29 degrees, as temperatures rebound after the rain-induced cooling.
On the weekend of the 30th and 31st, due to the influence of high-pressure systems, the weather nationwide is likely to be mostly clear. Daytime temperatures are expected to reach 30 degrees, which is similar to the average temperatures for this period.