Typhoon Songda (2011)

track of Songda

A weak non-tropical system formed within the Intertropical Convergence Zone on May 17, as it moved in a westward direction. On May 19, the JTWC reported that an area of low pressure had persisted about 510 km (320 mi) to the southeast of Yap. As the system moved towards the northwest under the influence of a subtropical ridge of high pressure, it rapidly consolidated in an area of light to moderate vertical wind shear. The JMA then started to monitor the system as a tropical depression later that day, before the JTWC designated it as Tropical Depression 04W early on May 20. The JTWC then reported later that day that the depression had intensified into a tropical storm with wind speeds of 65 km/h (40 mph), however, it later reported that it had overestimated the wind speeds and consequently lowered the storm's status to a tropical depression, based on observations from Yap island. Late on May 21, both the JMA and the JTWC reported that the depression had now become a tropical storm with the JMA naming it as Songda. Over the next couple of days, the system gradually intensified further while moving northwest into PAGASA's area of responsibility. PAGASA named it as Chedeng. At 12:00  UTC on May 24, the JTWC reported that Songda had intensified into a typhoon. 12 hours later, the JMA followed suit while the system was located about 800 km (500 mi) to the southeast of Manila in the Philippines. It rapidly intensified into a Category 5 typhoon. On the afternoon of May 29, Songda became extratropical south of Shikoku Island.[2] The extratropical remnants of Songda later crossed the International Date Line, which was later absorbed by another extratropical cyclone on June 4, and which later dissipated over Alaska.

Although Songda remained offshore, heavy rains within the typhoon's outer bands impacted the Philippines, causing significant flash flooding and landslides. Four fatalities are attributed to the system there.[3] Further north, Okinawa experienced intense wind gusts, measured up to 198 km/h (123 mph), along with torrential rain.[4] Extensive damage took place across the area with losses reaching ¥23.2 billion ($287 million);[5] however, there were no fatalities.[6] As it became extratropical, Songda brought heavy rains from Kyushu to eastern Honshu, causing significant flooding. At least 13 people were killed in the country and an estimated 400,000 had to be evacuated around Tokyo alone.[7][8]

Wikimedia Commons has media related to Typhoon Songda (2011).

• Digital Typhoon : Typhoon 201102 (SONGDA) - National Institute of Informatics