Koinu was a C1 tropical cyclone that formed in the Philippine Sea in 2023. The storm reached maximum sustained winds of 167 km/h (90 kt) with a minimum central pressure of 940 hPa. Tracking across the Philippine Seain the Western Pacific basin (, it potentially affected the Philippines, Taiwan and Japan. The storm traveled from approximately 14.2°111.3° to 22.2°143.8°, crossing a range of 8 latitude and 33 longitude.