Typhoon 6 and a seasonal rainy front have converged to bring heavy rainfall and flooding to western Japan and the islands [1].
This weather system disrupts critical transportation arteries and threatens residential safety, as the combination of a typhoon and a stationary front often leads to unpredictable and intense precipitation levels.
The storm's impact began as Typhoon 6 approached Okinawa and the Amami Islands between June 1 and June 2 [2]. In the Shikoku region, forecasts indicated precipitation levels reaching 300 mm [4]. The severity of the rainfall led authorities to issue a Level 5 emergency warning for flooding at the Kozagawa River in Wakayama Prefecture [5].
Transportation networks faced significant instability due to the rain. JR Central and JR West, the operators of the Tokaido and Sanyo Shinkansen lines, published their operational outlooks on June 2 [6]. The heavy rain along the Tokaido Shinkansen corridor, which connects Tokyo, Nagoya, and Osaka, created a high risk of train delays and cancellations [1].
Weather officials from the Japan Meteorological Agency monitored the system as it moved across the archipelago. While some reports indicated a reduced risk of warning-level rain for the Okinawa main island and Sakishima Islands, other data suggested the potential for severe rain stretching from Okinawa to the Tohoku region [2].
The convergence of these two systems created a corridor of intense moisture. This resulted in concentrated torrential rain that overwhelmed local drainage and river systems in several prefectures [1], [3].
“Typhoon 6 and a seasonal rainy front have converged to bring heavy rainfall and flooding to western Japan.”
The simultaneous arrival of Typhoon 6 and the rainy season front demonstrates the compounding effect of multiple weather systems, which can amplify flooding risks beyond the capacity of standard infrastructure. The potential for Shinkansen disruptions highlights the vulnerability of Japan's high-speed rail network to extreme precipitation, which often necessitates preemptive service suspensions to ensure passenger safety.
