Heavy rain to return to S. Korea with extreme downpours in southern regions

SEOUL – South Korea is bracing itself for another bout of heavy rainfall this week, just a day after powerful downpours swept through southern portions of the country.

According to the Korea Meteorological Administration (KMA) on Aug 4, a narrow band of concentrated rain clouds is expected to stretch across the country from north to south between Aug 6 and 7.

“Rain clouds resembling such a shape and pattern could bring another round of extreme, localised torrential rainfall – specifically focused on the already rain-stricken southern regions,” said KMA official Gong Sang-min at a press briefing on Aug 4.

Between Aug 3 and the morning of Aug 4, Korea’s southern region saw accumulated rainfall of beyond 190mm.

As of 10am, Muan, South Jeolla Province, had seen 289.6mm of rainfall, while Hapcheon, South Gyeongsang Province, and Gwangju had seen 212.7mm and 197.9mm, respectively.

As a developing low-pressure system passes over North Korea from the wee hours of the morning of Aug 6, rain will likely first be observed in Seoul and surrounding regions. The atmosphere is expected to become increasingly unstable as hot and humid air from the south continues to push northward – sparking additional showers in the southern region throughout the rest of the day.

From the afternoon of Aug 6, rain clouds are expected to move south, with heavy rain to persist until the morning of Aug 7.

Cooler, drier air flowing into the Korean Peninsula from the north-west is forecast to move southward, clashing with warm air flowing into the country from the south, creating unstable atmospheric conditions and ideal conditions for the formation of a long and narrow rain band.

“The cool, dry air from the north being resisted by the warm, moist air from the south can lead to the creation of strip-shaped rain bands, resulting in concentrated downpours over specific areas,” said Mr Gong.

“If the influence of the moist, hot air from the south and the influence of the dry, cold air from the north holds similar power, such differing air conditions could clash with each other and create ideal conditions for the formation of long and narrow rain bands.”

As of Aug 4, 30mm to 80mm of accumulated rain was expected to fall in the Greater Seoul region, which includes Incheon and Gyeonggi Province, as well as inland and mountainous areas of Gangwon Province and North and South Chungcheong provinces. North Jeolla Province may also see 10mm to 60mm of rain.

Though high temperatures are likely to subside after heavy rain on Aug 6, the decrease in temperatures would only be temporary, as heat wave watches, issued when apparent temperatures are expected to exceed 33 deg C, are expected to remain.

However, as cold, dry air continues to flow into the country from the north, the KMA added that there is a chance for tropical nights to cease from Aug 7 in Seoul, which saw 15 consecutive tropical nights from July 19 to Aug 2. THE KOREA HERALD/ASIA NEWS NETWORK