Typhoon Dujuan approaches the Tokyo region with the highest-level landslide warning issued for Izu Oshima

Typhoon Dujuan, the twenty-fifth named storm of Japan's season, made landfall on the Boso Peninsula in Chiba Prefecture, east of Tokyo, on September 21, carrying sustained winds of 126 kilometres per hour and gusts up to 180 kilometres per hour as it brought heavy rain across eastern Japan, with Level 4 danger warnings issued for some areas. The Japan Meteorological Agency issued a special landslide warning for Izu Oshima, its highest category, Jiji Press reported.

Flood and landslide warnings extend across eastern prefectures, and organisers of the Asian Games in Aichi prefecture postponed the equestrian eventing competition until Tuesday. As the storm crossed the country, authorities confirmed one death and one minor injury in Miyazaki Prefecture, in southern Japan, Bloomberg reported. Organisers closed Tokyo Game Show 2026 a day early because of the storm, and airlines cancelled flights serving the capital region.

A storm crossing the Tokyo metropolitan area halts rail, air and port movement in the largest urban economy in the world by output, and the cost sits mainly in lost activity and interrupted logistics rather than in destroyed property. Japanese non-life insurers have absorbed a rising frequency of these events, which they price into renewals, while the business interruption that follows a one-day shutdown, and the confirmed fatality in Miyazaki, are largely outside what property insurance captures and land directly on company results and public health accounting instead.