Typhoon 6 made landfall in southern Wakayama around 4:30 a.m. Wednesday, bringing intense rainfall and strong winds across Japan [1].

The storm's arrival coincides with the start of the rainy season in Shikoku, creating a combined weather event that has intensified precipitation and increased the risk of flooding throughout the region [1, 2].

In Wakayama, the Koya River was placed under a level five emergency flood warning [1]. Takuya Hosomi, a manager at the Japan Meteorological Agency's Forecast Division, said river flooding had already occurred and the situation corresponded to level five [1].

The storm's effects extended to the Kanto region, where the Zenpukuji River in Tokyo's Nakano and Suginami wards triggered a level four flood danger warning [1, 2]. Residents reported a sudden and drastic increase in wind and rain, with one resident saying the conditions were completely different from usual [1].

Infrastructure damage has been reported across several areas. Power outages occurred in multiple regions, including Tokyo [2]. Additionally, some sections of local train lines were suspended as the storm moved through the country [1].

Weather officials said the severity of the storm was due to the typhoon's strength and the presence of rain clouds carrying massive amounts of water vapor as they approached the Japanese archipelago [1].

“River flooding has already occurred and the situation corresponded to level 5.”

The intersection of a powerful typhoon with the onset of the rainy season in Shikoku creates a compounding disaster scenario. When tropical cyclones merge with seasonal monsoon patterns, the resulting precipitation often exceeds the capacity of urban drainage and river systems, as evidenced by the high-level flood warnings in both rural Wakayama and densely populated Tokyo.