ICHARM -- The International Centre for Water Hazard and Risk Management


July 2007: Typhoon No.4 and Seasonal Rain Front

  1. Typhoon No.4
    • A tropical storm developed into Typhoon No.4 by 3:00 on July 9 near the Caroline Islands and extremely increased in intensity, heading northwest in the sea east of the Philippines. On July 13, the typhoon headed north in the sea west to the main land of Okinawa.
    • By the 14th, the typhoon approached Kyushu keeping the same level of intensity, and landed on the Osumi peninsula in Kagoshima Prefecture around 14:00.
    • After the landfall to the 15th, the typhoon moved eastward along the southern coast of Shikoku island and the main land of Japan, gradually decreasing in intensity.
    • By 9:00 on July 17, the typhoon became an extratropical cyclone in the sea east of Japan
    • Okinawa and the Pacific side of Japan were hit by strong winds. In particular, a maximum wind velocity of 33 m/s was recorded at Kin in Kin Town, Okinawa Prefecture. On July 14, highest instantaneous wind velocities were recorded at some places, for instance, 55.9 m/s at Aburatsu in Nichinan City, Miyazaki Prefecture.
  2. Heavy Rain
    • From July 5-7, the seasonal rain front stayed over Japan and caused heavy rainfall in a wide area of the Kyusyu region and some areas of the Shikoku, Kinki and Tokai regions.
    • In particular, on the 7th, a 24 hour rainfall of 432 mm was observed at Tawarayama in Kumamoto Prefecture. Also, Twenty-four hour rainfalls were recorded highest in history at some places around the regions, for example, 324 mm at Kosa in Kumamoto Prefecture and 271 mm at Kuroki in Fukuoka Prefecture.
    • From July 10-12, heavy rain hit the Kyushu, Kinki and Tokai regions. On the 11th, particularly, an hourly rainfall of 107 mm was observed at Sata in Kagoshima Prefecture.
    • Highest 24 hour rainfalls were recorded at some places around the regions, for example, 353 mm at Sata in Kagoshima Prefecture and 202 mm at Doi in Shizuoka Prefecture.
    • On July 13, Typhoon No.4 approached and passed Okinawa, causing a heavy rainfall of over 200 mm.
    • Also, warm and humid winds blew in from the south towards the rain front lingering over the main land of Japan, causing heavy rain centering on the Pacific side of the western part of Japan.
    • Hyuga in Miyazaki Prefecture observed a rainfall of 399 mm in 24 hours, which was the highest 24 hour rainfall ever recorded.
    • From July 14-16, Typhoon No.4 veered east and moved along the Pacific coast of the main land of Japan. Because of that, heavy rain hit a wide area form western part of the main land to the southern part of the Tohoku region. A rainfall of over 500 mm was recorded in the Shikoku region and over 400 mm in the Tokai region.
    • The total rainfall of July 5-16 exceeded twice the July monthly average rainfall in many places of the Nan-sei Islands and the Kyusyu, Shikoku, Tokai and Kanto regions. In particular, a historical rainfall of 911 mm was recorded at Wanitsukayama in Miyazaki City, Miyazaki Prefecture.