The past month has seen the third highest amount of rain since the weather service began keeping track. This summer, more rain than usual is likely to fall in July and August due to the effects of the El Niño phenomenon.

According to the Korea Meteorological Administration’s weather data open portal on Jan. 1, the average cumulative rainfall nationwide last month was 193.4 millimetres. It was the third highest amount of rain after 1974 (212.1 mm) and 1997 (199 mm) since weather observations began nationwide in 1973. It was 33 times more than last year (5.8 mm), which was the lightest on record. Jeju Island received 408.1 millimetres of rain, the most on record.

In particular, a lot of heavy rain fell across the country on each of the golden holidays, including Children’s Day and Buddha’s Day스포츠토토. In addition, the so-called “rainy season myth” that it would rain for all but three days in July spread on social media, leading to a significant increase in sales of rainy season-related products. According to fashion platform W Concept, sales of rainy season products such as rain boots and aqua shoes increased more than 15 times from the same period last year from the 1st to the 30th of last month.

The recent large amounts of rain across the country are attributed to the frequent influx of moisture-laden air from the south. “The monsoonal winds originating from the Indochina Peninsula have provided a good channel for water vapour to move from southern China to Korea,” said Park Jung-min, a forecast analyst at the Korea Meteorological Administration. “As a result, stagnant fronts have formed, and much rain has fallen in the past three days.”

Rainy season starts in China and Japan…when in Korea?

Children with umbrellas walk at the Yakbamsan Village Ecological Village in Seoksan-ri, Gunwi-gun, North Gyeongsangbuk-do, as rain falls across the country on the 29th of this month. Yonhap News1
From June, the beginning of summer, the number of rainy days increases and the intensity increases. On the 1st and 2nd, a new stagnant front is expected to form, bringing heavy rain of up to 80 mm or more, mainly in the southern regions. By dawn on the 2nd, the coast of Gyeongnam and the midlands and mountains of Jeju are expected to receive 20 to 60 mm of rain, with many places receiving more than 80 mm. Jeonnam, southern Gyeongsangbuk-do, and inland Gyeongnam will also receive 10 to 40 mm of rain.

China and Japan have already entered the summer rainy season, with the rainy season beginning in some areas. Japan declared the start of the Baiu season late last month, mainly in southern regions such as Kyushu, while China is also experiencing heavy rainfall in its southern regions due to the Meiyu season. In China and Japan, the rainy season is called Meiyu and Baiu, respectively, and refers to the rain that falls when the plums, the fruit of the plum tree, open in May and June. In Korea, the rainy season usually starts on the 19th in Jeju, the 23rd in the south, and the 25th in central Korea.

Chances of rain in July and August are higher than normal

The probability of above-normal precipitation for June to August in East Asia. Areas in light blue are likely to receive more rain than normal. APEC Climate Centre
The prevailing outlook is for more rain than normal this summer as an El Niño event is forecast to develop. El Niño is a climate phenomenon in which sea surface temperatures in the eastern Pacific Ocean are more than half a degree above normal.

“Precipitation is expected to be above normal over the Korean Peninsula, western and northeastern China, and parts of northern Japan this summer,” the APEC Climate Centre said in its East Asia Seasonal Climate Outlook. Ten climate forecast models provided by meteorological offices around the world, including Australia and Canada, also predicted that June will be near normal precipitation, but July and August will have a higher probability of above-normal rainfall.

The Korea Meteorological Administration (KMA) also forecast normal to heavy rainfall in July. “In the case of El Niño, a low-pressure circulation is strengthened near Korea, which brings in a large amount of water vapour from the south,” said Kim Kyung-sook, head of the Climate Prediction Division at the Korea Meteorological Administration. “Based on past cases, there will be a tendency for heavy precipitation centred on the southern regions between mid-July and mid-August.”