TROPICAL CYCLONES IN 2006

Chanchu was the first tropical cyclone to necessitate the issuance of warning signals in 2006. It was also the first typhoon to form over the western North Pacific in 2006.

Chanchu developed as a tropical depression over the western North Pacific about 420 km west-southwest of Yap on 9 May and tracked mainly towards the west-northwest. It intensified into a severe tropical storm on 10 May and struck the central part of the Philippines the following day. In the fury of Chanchu, at least 37 people were killed in the Philippines where about 8 000 people had to flee their homes. Some 600 houses were destroyed, another 3 500 damaged and a ferry capsized.

On 13 May, Chanchu attained typhoon strength upon entering the South China Sea. Moving westwards for two days, it turned to the north on 15 May. Heading towards the south China coast, Chanchu strengthened further and the maximum sustained wind speed near its centre reached 185 km/h. Chanchu was the most intense typhoon on record to enter the South China Sea in May. In the South China Sea, several Vietnamese fishing boats capsized in the fury of Chanchu. At least 44 fishermen were killed and more than 160 reported missing. Chanchu took on a north-northeastward course on 17 May. It made landfall near Shantou the next day and weakened gradually thereafter. On 18 May, Chanchu rampaged through the coastal areas of southeastern China and entered the East China Sea. It became an extratropical cyclone that evening. The adverse weather brought by Chanchu inflicted severe damage in Guangdong and Fujian. Altogether, 19 people were killed, another four were injured and ten million people or more were affected in the two provinces. About 14 000 houses collapsed and over 190 thousand hectares of farmland were damaged. The direct economic loss was approximately RMB$ 7 billion. In Taiwan, Chanchu caused two deaths.

In Hong Kong, the Standby Signal No. 1 was issued at 9.40 p.m. on 15 May when Chanchu was 750 km to the south of Hong Kong. With Chanchu edging closer to Hong Kong, the Strong Wind Signal No. 3 was issued for the first time this year at 7.15 a.m. on 17 May, when Chanchu was about 250 km to the south-southeast. Locally, winds strengthened significantly and squally showers set in as Hong Kong came under the influence of Chanchu's outer rainbands.

Chanchu was closest to Hong Kong at around 2 p.m. on 17 May when it was centred about 220 km to the east-southeast. The lowest hourly sea-level pressure of 997.1 hPa was recorded at the Hong Kong Observatory Headquarters at 4 p.m. the same day. As Chanchu moved away, the No. 3 Signal was replaced by the Standby Signal No.1 at 9.15 p.m. on 17 May. All tropical cyclone warning signals were cancelled at 4.40 a.m. the next day.

During the passage of Chanchu, a duty lifeguard was injured as the guard post collapsed in strong winds in Tseung Kwan O. An elderly was hit and injured by a fallen flower pot in east Kowloon. Another person was reported fallen into the sea at Siu Sai Wan and suffered injuries. Three persons were injured on board the jetfoil bound for Macau. Minor flooding occurred in Sheung Wan as high tide together with storm surge brought sea levels to reach 2.8 metres at the Victoria Harbour. Several cases of fallen trees and scaffoldings were reported. At the Hong Kong International Airport, more than 60 flights were cancelled and another 14 delayed. A yacht sank in Sai Kung. Several ferry services were suspended.

Information on wind, rainfall and tide during the passage of Chanchu is given in Tables 3.1.1-3.1.3. Figures 3.1.1-3.1.4 show the track of Chanchu, rainfall distribution in Hong Kong, cloud imagery and radar imagery respectively.

- Top -