After deadly flooding struck the Korean Peninsula and Japan earlier this month, another dose of heavy rainfall renewed flooding across the region this week.
This rain arrived as a one-two punch during the second half of the week.
"Two different storms moving along a semi-stationary front, known as a mei-yu front, sent bouts of heavy rain from eastern China to the Korean Peninsula and Japan through the second half of the week," said AccuWeather Meteorologist Maura Kelly.
Rain, which began in eastern China at the start of the week, moved into parts of the Korean Peninsula by midday Wednesday, especially in southern parts of South Korea.
By Wednesday evening, downpours washed over portions of western Japan, including northern Kyushu, Shikoku and western parts of Honshu.
The second, and more powerful, storm followed the first one rather quickly, bringing another dose of heavy rain to North and South Korea on Thursday and Thursday night.
"The second storm followed a path directly toward the Korean Peninsula, with the heaviest rain arriving late in the afternoon and continuing overnight," Kelly added.
In North Korea, rainfall totals from Wednesday and Thursday reached 108 mm (4.26 inches) in Kaesong and 53 mm (2.08 inches) Haeju.
On Friday, rescue efforts were underway at the Anju Coal Mine, located north of Pyongyang, North Korea, after a section of the mine prone to flooding collapsed, trapping at least a dozen miners, reported the Daily NK.
The mining company released a statement that they were concerned about the possibility of collapse due to the recent heavy rain, but they could not stop production due to a lag behind another mining company, added the Daily NK.
South Korea has taken the brunt of the rain on with reports of 50-100 mm (2-4 inches) of rainfall on Wednesday and Thursday common across the country. Uljin-eup, South Korea, reported the highest rainfall total with 228 mm (8.98 inches). In Seoul, 103 mm (4.06 inches) of rain fell over the course of two days.
Busan, South Korea, reported 80 mm (3.15 inches) of rain falling in 12 hours with the bulk of the rain falling around the same time as high tide on Wednesday night. Rainfall in the city totaled 177 mm (6.97 inches) from Wednesday to Thursday. This had disastrous effects across the coastal city.
Photos have emerged of floodwaters filling Busan Station, and passengers were forced to stand on their seats as water rushed into subway trains. A car was also seen completely submerged in a parking garage.
According to a local news report, around a dozen people were rescued from their vehicles as an underground roadway filled with water. Two people died while being transported to the hospital.
There is a report of an additional death and numerous injuries due to flooding, according to KBS News.
Dozens were evacuated from an apartment building in Dong District of Busan after floodwaters breached the building. There are also reports of landslides and collapsed retaining walls that led to damage across the city.
"As the heaviest rain tapered off across South Korea on Friday, flooding downpours moved into western Japan on Friday," stated Kelly. "Areas of heavy rain continued across western and central Japan through Saturday."
Between both storms, the double dose of heavy rain means that rainfall totals are likely to climb to 50-100 mm (2-4 inches). An AccuWeather Local StormMax™ of 200 mm (8 inches) will be possible, especially in the higher elevations.
"This much rain, especially after an already wet stretch of weather, is falling on very saturated ground," said Kelly.
Because of this, less rain will be needed to cause flooding issues, and trees may be more easily toppled or uprooted. Mudslides will be a major concern in the hilly and mountainous terrain.
According to Kelly, the storm system will linger in the area keeping areas of rain over Korea and Japan through at least Sunday.
The flood-weary areas threatened by these next rounds of heavy rain have experienced dangerous flooding from the torrential rainfall earlier this month.
On Monday, reports came in of immense rainfall across parts of North Korea, totaling over 50 mm (2 inches) in many locations. Hamheung had the highest rainfall total with 87 mm (3.43 inches) of rain falling in 24 hours.
In mid-July, more than 200 mm (8 inches) of rain fell in parts of southern South Korea, killing several people and causing traffic accidents.
An astounding 277 mm (10.9 inches) of rain fell in Sancheong of South Gyeongsang Province, according to the Korea Meteorological Administration (KMA) and 210 mm (8.3 inches) of rain in the town of Geoje, just west of Busan.
In Japan, the island of Kyushu was badly battered by heavy rain that moved through the area during late June and early July. A total of 71 people have been confirmed dead due to the floodwaters, most coming from the hard-hit prefecture of Kumamoto.
According to a report from The Japan Times, about 2,000 people are still living in shelters after heavy rain, flooded rivers and landslides forced residents from their homes earlier in the month.
Recovery efforts have been slow in some remote locations as numerous roads and bridges have been washed away. More rain on the way can lead to additional delays and flooding concerns this week.
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