HONG KONG was warned last night to brace for the possibility of its third battering in five weeks, with rain and winds whipped up by tropical storm Cam forecast to draw closer. The Observatory raised typhoon signal No 3 at 3.40pm yesterday, saying the storm was expected to pass within 100km of the SAR by today. Senior scientific officer Mok Hing-yin said Cam was making unpredictable changes of direction reminiscent of the wild behaviour of Typhoon York, which killed two people when it struck suddenly 10 days ago. 'It's difficult to compare one tropical storm with another, but we can say Cam is also showing rather erratic movements,' he said. He said the storm had initially been travelling east, then turned to head north. At 11pm Cam, which was downgraded to a tropical storm last night, was 160km east-southeast of Hong Kong and forecast to move north or northwest slowly. Mr Mok said the outer edge of the storm had already brought rain to the eastern part of Hong Kong, and forecast strong winds and squally showers for today. Typhoon York, the fiercest storm to hit Hong Kong in 16 years, struck with surprising force on September 16, injuring 500 people and damaging office blocks. On August 22, Typhoon Sam brought pelting rain and strong winds during which a China Airlines MD-11 jet crashed at Chek Lap Kok, killing three people and injuring 212. Today's Chinese Art Market and Chinese Food Plaza, due to have been held in the Hong Kong Cultural Centre piazza from noon, has been cancelled because of the weather.