Tropical Storm Dujuan may hit Japan over upcoming Silver Week holiday

Tropical Storm Dujuan has formed near the Mariana Islands and may bring rainfall during the Silver Week holidays next week, according to the Japan Meteorological Agency (JMA).

The JMA said Wednesday night that a tropical cyclone that had formed near the Mariana Islands had become a tropical storm, known as taifū No. 25 in Japan. It was moving north-northeast at a speed of 15 kilometers per hour.

Dujuan is expected to develop into a large-scale severe tropical storm. A severe tropical storm brings wind speeds between 25 and 33 meters per second, which can make walking and driving difficult and cause damage to trees and signs, according to the JMA. As a large-scale storm, it will have a 30-knot (56 kph) wind radius of between 500 and 800 km.

The storm is forecast to move toward the Ogasawara Islands on Friday and make landfall there around Saturday morning, before moving up toward the Izu Islands on Sunday.

On Monday, the center of the storm is expected to be around 100 km off the coast of the Boso Peninsula and about 180 km from central Tokyo, putting the Kanto region well within its radius. It is then expected to move northeast, affecting part of the Tohoku region early next week.

The tropical storm could dampen plans for Silver Week, a five-day alignment of consecutive holidays that has not occurred in 11 years. The JMA foresees rain for much of eastern and northern Japan on Sunday and Monday. The Japan Weather Association, a private forecaster, predicts heavy rain in the Kanto region and nearby coastal prefectures, including up to 300 millimeters of rain per day in Chiba Prefecture.

The storm will likely continue what has been a historically rainy and cloudy month so far due to low pressure and an autumn rain front. The JMA announced on Tuesday that from Sept. 1 through Sept. 14, the Kanto-Koshin and Tokai regions had each experienced around only 30% of the sunlight normally received in the first half of September, the lowest numbers since records began in 1961.

Meanwhile, the Kanto-Koshin region also set a record for rainfall over the same period, at 365% of the usual amount. This was the highest total since the JMA began logging such figures in 1946.