As South Korea enters the first weekend of April, the nation is bracing for a sweeping bout of spring rain and powerful winds that are set to impact nearly every region from Jeju Island in the south to Seoul and the northern provinces. According to the Korea Meteorological Administration (KMA), the weather system began making its presence felt on April 3, 2026, with rain starting in Jeju during the afternoon and spreading northward, promising a wet and blustery Saturday for millions.
By late evening on April 3—between 9 p.m. and midnight—the rain is expected to reach the Seoul metropolitan area, Incheon, and Gyeonggi Province, extending to most of the country by the early hours of April 4. The KMA has warned that the bulk of the rainfall will occur during the morning, although some eastern and mountainous areas may continue to see showers until late afternoon. In particular, the inland and highland regions of Gangwon and Chungbuk are likely to experience lingering precipitation well past midday, as reported by Global Economic.
Forecasts point to a varied deluge across the peninsula. Southern Gyeonggi, central and southern Gangwon, Chungcheong, Jeonbuk, Daegu, Gyeongbuk, Ulleungdo, and Dokdo are all expected to receive between 10 and 40 millimeters of rain. Meanwhile, Seoul, Incheon, northern Gyeonggi, and northern Gangwon can expect slightly less—around 5 to 20 millimeters. The West Sea’s five islands are forecast for 5 to 10 millimeters. Yet, the heaviest downpours are likely to hit Jeju (excluding its northern region) and the southeastern coastal areas, including Busan, Ulsan, southern Gyeongnam, Jeonnam’s southeastern coast, and the Jirisan region, where totals could soar to 30–100 millimeters, with Jeju’s mountainous zones potentially exceeding 150 millimeters, according to Inews24.
Rainfall intensity is expected to be particularly fierce during the late night of April 3 and the early hours of April 4. Jeju’s mountainous and mid-mountain regions may see hourly rates of 20–30 millimeters, and similar rates are predicted for the southeastern coast and Jirisan area during the early morning. The KMA has issued heavy rain warnings for Jeju’s mountains and advisories for other vulnerable areas, urging residents and travelers to remain alert.
But it’s not just the rain that has authorities on edge. Strong winds are forecast to accompany the downpours, posing risks to infrastructure, transportation, and safety. The metropolitan region, West Sea islands, and other exposed areas should expect gusts up to 55 km/h (15 m/s), while the southern coasts and Jeju could see even more ferocious winds. Along the southern coasts of Jeonnam and Gyeongsang, gusts may exceed 70 km/h (20 m/s) from the early hours of April 4, and Jeju’s mountain areas could experience winds as high as 90 km/h. The KMA has cautioned that such conditions may disrupt ferry and flight operations, especially in Jeju and the south, and has advised people to check transportation updates before traveling.
Sea conditions are also expected to deteriorate rapidly. The central offshore areas of the West Sea will see strong winds of 6–13 m/s and waves rising to 1.0–2.5 meters from the night of April 3 through April 4. Mariners and fishing vessels are urged to exercise extreme caution. Furthermore, the rapid passage of a low-pressure system over the sea may trigger a meteorological tsunami (seiche), leading to high waves overtopping coastal roads and breakwaters in Jeju, Jeonnam, and Gyeongnam between late April 3 and the morning of April 4. Swells could also bring powerful waves to Jeju and the southern coast, increasing the risk of coastal flooding and property damage.
Despite the inclement weather, temperatures are forecast to remain slightly above the seasonal average. Morning lows on April 4 will range from 8 to 13°C, with Seoul, Incheon, and Suwon all starting the day at 11°C. Daytime highs will climb to between 13 and 21°C across the country, with Seoul expected to reach 18°C, Incheon 16°C, Suwon 16°C, Daejeon 18°C, Gwangju 17°C, Daegu 19°C, Ulsan 20°C, and Busan 19°C. The average for early April typically sees lows of 0–8°C and highs of 14–18°C, so this weekend will feel a touch warmer, perhaps a welcome note for those longing for spring’s embrace.
Air quality is not expected to deteriorate significantly during the rain event. Fine dust and ultrafine dust concentrations are forecast to be ‘moderate’ in the morning and ‘good’ in the afternoon for most regions, with Busan, Ulsan, Gyeongnam, and Jeju enjoying especially clean air. The KMA’s latest bulletins suggest that the rain will help wash away airborne particulates, offering a brief respite from pollution concerns.
Still, the combination of rain, wind, and reduced visibility will make for hazardous conditions on the roads. The Korea Meteorological Administration emphasized, “In areas where it is raining, roads will be slippery and visibility will be limited, so please pay special attention to traffic safety.” This advice is echoed in local news outlets, which have urged drivers and pedestrians to exercise caution, especially during the morning rush when the rain will be heaviest.
The timing of sunrise and sunset on April 4 will be 6:14 a.m. and 6:57 p.m., respectively, offering a full day for the weather to make its mark. For those planning outdoor activities or travel, officials recommend monitoring the latest forecasts and heeding any advisories or warnings issued by local authorities.
Looking ahead, the weather is expected to improve on Sunday, April 5. The skies will remain mostly cloudy in the morning but are forecast to clear as the day progresses. Morning lows will dip to 2–9°C, while daytime highs will settle between 14 and 20°C, bringing a return to more typical spring conditions across the peninsula.
In the midst of this meteorological drama, nature’s resilience is quietly on display. On April 3, as the first drops of rain fell, blue new buds were spotted on a sumac tree at Icheon Seolbong Park—an understated reminder that spring’s renewal continues, even when the weather turns wild.
As South Korea navigates another bout of spring rain and wind, residents are reminded to stay vigilant, look out for one another, and take solace in the knowledge that clearer skies are just around the corner.