From the late night of the 17th, rain or snow is expected to start in the metropolitan area and Chungnam, expanding nationwide by the 18th. A cold snap will accompany this, causing morning temperatures to drop below freezing and daytime temperatures to remain low.
According to the Korea Meteorological Administration, amidst a strong cold wave, heavy snow accompanied by strong winds, thunder, and hail is forecast across the country. Cold air from the Arctic, with temperatures dropping to minus 40 degrees Celsius in the northwestern upper air, will move south, causing rain and snow to start in the metropolitan area and Chungnam late on the 17th.
By the 18th, most regions are expected to experience rain or snow. This precipitation is expected to start clearing from the late afternoon on the 18th in the metropolitan area and Honam, with most areas clearing by night.
Currently, a preliminary heavy snow warning has been issued for most parts of the country, excluding coastal areas such as Seoul. A preliminary strong wind warning is also in effect for most coasts and the western inland and Jeju Island.
This preliminary heavy snow warning across the country in late March is the first such issuance in seven years since 2018. The expected snowfall is as follows: 10-30 cm (more than 40 cm in some areas) in the mountainous areas of Gangwon and the east coast; 10-20 cm in northeast Gyeongbuk Mountains, northern Gyeongbuk east coast, Ulleungdo, and Dokdo; 5-15 cm (more than 20 cm in some areas) in inland Gangwon; 5-10 cm (more than 15 cm in some areas of northwest and eastern Gyeonggi) in the metropolitan area, West Sea 5 Islands, northern inland Gyeongbuk, and southern Gyeongbuk east coast.
For regions such as Chungcheong (excluding southern Chungnam west coast) and eastern Jeonbuk, 3-10 cm (more than 15 cm in some areas) is expected. In the eastern inland Jeonnam, Daegu, southern inland Gyeongbuk, Ulsan, western inland Gyeongnam, and mountainous areas in Jeju Island, snowfall of 3-8 cm (more than 10 cm in some areas) is anticipated. For southern Chungnam west coast, Gwangju, Jeonnam (excluding eastern inland), western Jeonbuk, Busan, central inland Gyeongnam, and eastern inland Gyeongnam, snowfall of 1-5 cm is expected, with around 1 cm expected in the southern coastal areas of Gyeongnam and mid-mountain areas of Jeju Island.
With the cold air moving in from the north, morning temperatures across most regions are expected to remain below freezing for the time being, with the morning low on the 18th forecast to be between minus 3 and 3 degrees Celsius. Daytime highs are projected to remain between 3 and 9 degrees Celsius.
The expected minimum and maximum temperatures in major cities are as follows: Seoul, Incheon, Daejeon, and Daegu will have 0 degrees and 6 degrees Celsius respectively, Gwangju will have 1 degree and 6 degrees, Ulsan 1 degree and 8 degrees, and Busan 3 degrees and 8 degrees.