Hong Kong was bracing on Sunday for this year's most powerful typhoon, with government meteorologists warning of severe flooding created by a double whammy of powerful winds and exceptionally high tides.
Typhoon Usagi, the strongest storm to hit the Western Pacific this year, is expected to hit the Asian financial centre late on Sunday and early on Monday.
The Hong King observatory posted a No. 3 signal warning of strong wind late on Saturday and was expected to raise the storm signal later on Sunday.
The storm posed a severe threat to the city, the observatory said.
China's National Meteorological Center issued its highest alert, warning that Usagi would bring gales and downpours to southern coastal areas, the official Xinhua news agency said.
More than 80,000 people had moved to safety in Fujian province and authorities had deployed at least 50,000 disaster-relief workers, it said.
Major Chinese airlines cancelled flights to cities in the southern provinces of Guangdong and Fujian while shipping was suspended between the Chinese mainland and Taiwan, Xinhua reported.
In Hong Kong, Cathay Pacific Airways Ltd, the city's main airline, and its unit Hong Kong Dragon Airlines Ltd, will cancel all flights into and out of the international airport from 6 p.m. (1000 GMT) on Sunday.
If a No. 8 storm signal remain in place after 7 a.m. on Monday (2300 GMT on Sunday), the Hong Kong stock exchange will be closed for at least part of the day.
Financial markets, schools, businesses and non-essential government services close when a No. 8 storm signal is hoisted, posing a major disruption to business in the former British colony.
Typhoon Usagi lashed the east and south coasts of Taiwan with heavy rain and wind on Saturday after slamming into the Philippines' northernmost islands where it cut communication and power lines and triggered landslides.