On September 5, 2025, the Japan Meteorological Agency announced the formation of a 'linear rainfall band' over Shizuoka Prefecture, leading to torrential rain within a short period, as Typhoon No.15 passed. This weather pattern brought warnings for landslides and flooding. By 1 PM, Typhoon No.15 was moving northeast at a speed of approximately 60 km/h, with central pressures at 994 hPa and maximum wind speeds of 20 meters per second. Reports highlighted high rainfall levels, such as 120 mm/hour near Kakegawa City and 110 mm/hour near Yoshida Town. Additionally, tornado activity was noted, prompting cautionary advisories for Shizuoka's central, eastern, and western regions.