Starting tomorrow, the 20th, which is Daehan ("the great cold") on the seasonal calendar, morning temperatures in most regions nationwide are expected to drop more than 10 degrees from today, extending a severe cold snap.
According to the Korea Meteorological Administration on the 19th, cold air will begin to flow in from the northwest after midday, and the temperature drop will steepen from night. In particular, cold wave advisories will take effect at 9 p.m. on the 19th for the central region, Jeolla region, and North Gyeongsang.
As temperatures plunge overnight, the entire Korean Peninsula is expected to come under the grip of a severe cold snap starting on the 20th. Morning temperatures will be about 10 degrees lower than today, and about 15 degrees lower in eastern Gyeonggi and inland and mountainous areas of Gangwon.
Morning lows on the 20th are forecast at -17 to -3 C, with daytime highs at -4 to 6 C. Morning temperatures in Seoul will be -13 C, Daejeon -11 C, Gwangju -6 C, and Busan -3 C, leaving most inland regions below freezing. The central region will fall to -10 C or lower, and inland and mountainous areas in northern Gyeonggi and Gangwon will drop to around -15 C.
The cold snap will peak on Wednesday the 21st, with morning temperatures at -18 to -4 C and daytime temperatures down to -7 to 3 C. Morning lows will be around -15 C in the central inland, northern Gyeonggi, and inland and mountainous areas of Gangwon, and the southern region will also be cold at -10 to -5 C. Strong winds will make it feel 5 to 10 degrees colder than the actual temperature.
On the 22nd, morning temperatures will be -18 to -5 C and daytime -7 to 2 C; on the 23rd–24th, morning -14 to -3 C and daytime -2 to 5 C, continuing colder than average. From the 25th to the 28th, mornings will be -13 to 0 C and daytime -3 to 7 C, rising somewhat but still below the average (morning -10 to 0 C, daytime 1 to 8 C).
There is also snow in the forecast. Late at night on the 20th, light snow flurries are expected along the West Sea coasts of South Chungcheong and Jeolla and on Jeju Island, and from the 21st, snow will fall intensively along the Jeolla West Sea coast, southern inland North Jeolla, central inland Gwangju and South Jeolla, and mountainous and mid-mountain areas of Jeju. Expected snowfall is 2–7 cm on the southern North Jeolla and South Jeolla West Sea coasts, 5–15 cm on Ulleungdo and Dokdo, and 5–10 cm in the mountains of Jeju. In areas where snow accumulates, there is a high chance of black ice and icy roads, so traffic safety is advised.
Risks from strong winds and high waves will also increase. From the afternoon of the 19th along the West Sea coast and Jeju's coast, and from night along the Gyeongsang coasts, strong winds with instantaneous speeds around 70 kph may blow. At sea, waves will run 1.5–4.0 meters, with the open sea reaching more than 5.0 meters. From the 20th, strong swells along the East Sea coast will raise the risk of coastal safety accidents.
Farmers should also prepare for crop and livestock damage. Operate heating in greenhouses and livestock sheds, and check water pipes, boilers, and aquaculture water levels to prevent burst pipes and cold-related deaths.
The Korea Meteorological Administration urged the public to take special care with safety and health to prevent damage from the cold wave, snow, icy roads, strong winds, and dry conditions over the next two days.