Extremely heavy rain hits Yakushima Island, Japan – 420 mm (16.5 inches) in 12 hours

​A warm and humid air current blowing from the east brought extremely heavy rain to Japan's southern Yakushima Island on Saturday, May 18, 2019. More than 12 000 residents were asked to evacuate immediately.

According to the Japan Meteorological Agency (JMA), rainfall in Yakushima reached 50 mm (1.9 inches) per hour. Some areas recorded more than 420 mm (16.5 inches) in 12 hours to 11:00 UTC.

In the southern part of the town, radar analysis of late afternoon showers recorded 120 mm (4.7 inches) per hour.

According to the NHK, around 12 400 people were asked to evacuate their homes in all parts of Yakushima Town in Kagoshima Prefecture.

Heavy rain caused floods and landslides, stranding 314 people on Mt. Miyanoura – a world natural heritage site. They were forced to spend the night in the vehicles and a mountain cabin. Rescuers reached them on Sunday.

The meteorological agency said that heavy rains felt at a level only seen once time every 50 years. The agency also issued a warning alert against landslides and warned more heavy rain is expected through Tuesday, May 21. Up to 50 mm (1.9 inches) of rain per hour in some areas of western and eastern Japan and up to 200 mm (7.8 inches) in 24 hours in Kinki and Shikoku, western Japan.

This event seems pretty similar to Yonaguni, Okinawa extremely heavy rainfall event of May 13, 2019, when 367 mm (14.4 inches) of rain fell in just 6 hours. 276.5 mm (10.88 inches) fell on Yonaguni in a three-hour period from 06:10 JST – the heaviest since detailed records began in 2003.

Featured image credit: ANN