South Korea’s Ministry of Interior and Security said three of the dead were trapped in a flooded semi-basement. Nine others were injured and at least seven people are still missing, the ministry said.
A total of 422 millimeters (16.6 inches) of rain has fallen in parts of Seoul since midnight local time Monday, prompting authorities to raise the highest level 3 emergency alarm. The city recorded 141.5 millimeters (5.6 inches) of rain per hour — the highest rate since authorities began tracking records.
More heavy rain is forecast to move through Seoul through Thursday, potentially leading to additional flash flooding in the region.
Heavy rain warnings are in effect in the metropolitan area and Gangwon-do, where rainfall of 50 to 100 millimeters (2-4 inches) per hour is possible, according to the Korean Meteorological Administration.
Photos from across the city during Monday’s flash floods show people wading up to their thighs in water on roads.
Although the water had largely abated by Tuesday morning, cars and buses remained scattered on roads and sidewalks, blocking morning traffic.
In some parts of Seoul, sewers were receding and water was flowing back into streets and subway stations, according to the Seoul Metro. A number of metro stations were closed due to flooding, causing the lines to be temporarily interrupted Monday evening. On Tuesday morning, the authorities were still busy reopening the stations.
Several regions south of the Han River were hardest hit, including the affluent, modern Gangnam district, where some buildings and shops were flooded and lost power.
About 800 residents were evacuated to schools and gyms or voluntarily sought shelter in local community centers as floods hit more than 700 homes and shops, authorities said.
He also pointed to the need to overhaul the country’s disaster management system, as extreme weather events are expected to become more frequent as a result of the climate crisis.
Many countries in East Asia are now experiencing more intense daily rainfall, with summer monsoons expected to become stronger and more unpredictable as the Earth warms, according to the Intergovernmental Panel on Climate Change.
According to DailyExpertNews meteorologists, more rounds of heavy rain will hit Seoul on Tuesday evening and continue through Thursday morning before ending Thursday afternoon.
The already flooded areas could receive another 300 millimeters (11.8 inches) of rain – which could contribute to further flooding and mudslides.
Seoul has an average of 348 millimeters (13.7 inches) of rain in August — the wettest month of the year there. Several locations recorded so much rain in just one day.