Monsoon rains to drench Korea all week, with heat spikes in between

Monsoon rains are forecast to continue across much of South Korea throughout this week. A stationary front will bring heavy downpours to many areas, while regions where the rain temporarily eases will face sweltering heat.

According to the Korea Meteorological Administration on Monday, rain will fall nationwide through Tuesday, with particularly heavy and sustained precipitation expected in central regions including the Greater Seoul area and the Chungcheong region. In southern parts of the country, the rain may briefly stop or weaken in some areas.

Forecast rainfall totals for Monday are: 20–60 millimeters for the Greater Seoul area; 5–40 mm for inland and mountainous areas of Gangwon Province; 5–20 mm along the Gangwon east coast; 20–80 mm for the Chungcheong region; 5–40 mm for the Jeolla region; 20–60 mm for central and northern North Gyeongsang Province; 5–40 mm for Daegu and southern North Gyeongsang Province; 5–20 mm for inland South Gyeongsang Province; 5–10 mm for Ulleungdo and Dokdo; and 5–20 mm for Jeju Island.

The west coast of South Chungcheong Province is forecast to receive particularly intense rainfall of 20–30 mm per hour between early morning and morning on Monday.

On Tuesday, strong rain accompanied by gusts, thunder and lightning is expected to hit central regions.

Tuesday will also bring 30–80 mm of rain to the Greater Seoul area and Gangwon Province. Some areas — including northern Gyeonggi Province, the five West Sea islands and northern inland Gangwon — could receive more than 120 mm. Rainfall of 20–30 mm per hour is expected in the Greater Seoul area and Gangwon Province from early morning through the morning hours.

The stationary front's influence will persist beyond that. Skies will remain mostly overcast nationwide Wednesday and Thursday, with rain coming and going throughout both days. Most of the country except South Gyeongsang Province and Jeju Island can expect rain on Friday. The Chungcheong region will see rain continue through Saturday morning, while the Greater Seoul area and Gangwon Province will remain wet through Saturday afternoon.

Oppressive heat will accompany the ongoing monsoon rains. Temperatures are expected to remain near or slightly above seasonal norms for now, and high humidity in areas where rain pauses will push the heat index significantly higher. Afternoon highs in some areas could reach 37 degrees Celsius on Tuesday and Thursday.

Heavy rain over the past weekend caused damage across the country. As of 4 a.m. Monday, the Central Disaster and Safety Countermeasures Headquarters under the Ministry of Interior and Safety had logged 828 damage reports from heavy rain nationwide.

By type, 256 reports involved flooded homes and roads, while 572 involved landslides and rockfalls. No casualties have been reported from the rains so far.

Cumulative rainfall from Friday through 5 a.m. Monday was highest in Yeongju, North Gyeongsang Province, at 206.8 mm. It was followed by Paju in Gyeonggi Province at 197.5 mm, Dongducheon in Gyeonggi at 195.5 mm, Yeoncheon in Gyeonggi at 189.5 mm, Pocheon in Gyeonggi at 185.5 mm, Cheorwon in Gangwon Province at 171.1 mm, Yangju in Gyeonggi at 170.5 mm, Gimpo in Gyeonggi at 167.0 mm, and Gangseo in Seoul at 164.5 mm.

The agricultural sector also sustained damage. Some 41.6 hectares of crops — including chili peppers, soybeans, sesame, apples and cucumbers — were flooded, an area equivalent to roughly 58 soccer fields. Flooded farmland totaled 7.1 hectares. Eight power outages and two communications disruptions were reported in Uiseong and Andong in North Gyeongsang Province, though most have since been restored.

Residents were also evacuated. A total of 557 people from 374 households across 20 cities and counties in six metropolitan and provincial areas temporarily evacuated, with 119 still staying at temporary housing facilities or the homes of relatives.

The Central Countermeasures Headquarters had activated its Level 1 emergency response at 9 p.m. Friday. The following day, it raised the heavy-rain crisis alert from Caution to Alert and activated a Level 2 response.

The Korea Meteorological Administration urged the public to prepare for landslides, rockfalls and river flooding, as the ground has already been weakened by heavy rain, and to guard against heat-related illness in areas under heat advisory.