Typhoon Usagi (2013)

Typhoon Usagi (international designation: 1319, JTWC designation: 17W, PAGASA name: Odette) is currently a powerful tropical cyclone which is affecting the province of Guangdong in China, and nearby Hong Kong and Macau. It is the third typhoon and the nineteenth tropical storm of the 2013 season in the northwest Pacific.

Meteorological history
On September 15, a tropical disturbance or a low-pressure area formed east of Luzon, and it was upgraded to a tropical depression by the Japan Meteorological Agency (JMA) early on the next day. On September 16, although the low-level circulation center was partially exposed, the Joint Typhoon Warning Center (JTWC) still issued a Tropical Cyclone Formation Alert on the consolidating system because of strong diffluence, as well as the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) upgraded the system to a tropical depression and named it Odette. Late on the same day, JMA upgraded the system to a tropical storm and named it Usagi; at the same time, JTWC upgraded it to a tropical depression, owing to a tropical upper tropospheric trough (TUTT) cell located to the east in association with an anticyclone enhancing the outflow in the eastern and southern quadrants. On September 17, JTWC upgraded Usagi to a tropical storm, as the system continued to consolidate and wrap tighter when slowly tracking westward along the extreme southern periphery of the subtropical ridge.

Early on September 18, JMA upgraded Usagi to a severe tropical storm; at noon, both JMA and JTWC upgraded Usagi to a typhoon, as deep convection had completely wrapped around a developing eye with radial outflow and low vertical wind shear. On September 19, Usagi began explosive intensification and formed a 15 nmi round eye; as the result, JTWC upgraded Usagi to a super typhoon with category 5 strength on the Saffir–Simpson hurricane wind scale at noon. On September 20, Usagi began the eyewall replacement cycle with a 40 nmi inner eyewall and a 100 nmi outer eyewall separated by a clearly-defined moat. Due to land interaction between Taiwan and Luzon, Usagi began to weaken late on the same day, as well as JTWC downgraded it to a typhoon early on September 21.

Impact
At least two people, a 50-year-old man and a 20-year-old woman, were killed when they drowned when a passenger boat capsized off northeastern Aurora province in the Philippines, and two others were missing. Cathay Pacific Airways and Dragonair said flights on 21 September were unaffected, but for one canceled flight. However, both airlines announced that flights to and from Hong Kong International Airport would be cancelled starting 6 p.m. September 22 and resume the next day if conditions allow. In Taiwan, more than 3,000 people were evacuated from flood-prone areas and mountainous regions. Some mountain roads were blocked by landslides, and power outages suspended some train service.

In response to the storm's approach Hong Kong, the Hong Kong Observatory issued the Storm or Gale Wind Signal No. 8 at 18:40 local time. It made landfall near Shanwei of the Chinese Guangdong province, and is now drifting westward as a strong typhoon.

In China alone it has caused about 7,100 homes to collapse and resulted in direct economic losses of 3.24 bln yuan.

At least 33 people have died in Asia, in this 25 deaths occurred in Guangdong province of south China.

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