Thai Airways International (THAI) and Air Asia on Sunday cancelled or postponed a number of flights to Hong Kong due to the impact of Typhoon Usagi.
THAI announced that four flights between Bangkok and Hong Kong were cancelled. They include TG606, TG607, TG638 and TG639.
The national carrier also called off flight TG608 from Phuket to Hong Kong and flights TG752 and TG753 between Bangkok and Macau.
Flight TG628 (Bangkok-Hong Kong-Seoul) will be rerouted as Bangkok-Seoul. Flight TG629 (Seoul-Hong Kong-Bangkok) has been postponed indefinitely.
For further information from THAI, travellers can call its contact centre at 02-356-1111 around the clock or visit www.thaiairways.com.
Air Asia also announced the cancellations of the Hong Kong and Macau-bound flights on its Facebook page.
From Air Asia's Facebook page
Typhoon Usagi, the most powerful storm of the year, unleashed torrential rain and ferocious winds on Taiwan on Saturday, leaving tens of thousands without power after claiming at least two lives in the Philippines.
Usagi -- which means rabbit in Japanese -- packed winds of 165 kilometres per hour (103 MPH) as it closed in on China's densely populated Pearl River Delta, forcing some residents in vulnerable areas to tape up windows and stock up on supplies.
The Hong Kong Observatory, issuing the second of a five-step tropical cyclone warning, said it was likely to bring "severe" disruption to the city with transport systems affected and expectations of high waves and localised flooding.
Cathay Pacific said it was cancelling all flights from 6pm (1000 GMT) Sunday. At the Chek Lap Kok airport, airline counters were besieged by anxious passengers hoping to rebook on earlier flights.
A Hong Kong ship (centre right) is brought into the typhoon shelter at Aberdeen harbour, already filled with anchored vessels, ahead of the arrival of Typhoon Usagi on Sunday. (AFP Photo)
Hong Kong's Airport Authority said that by the end of Sunday, it expected to see 376 flights cancelled by Cathay and other airlines.
The airport in Hong Kong is closed until Monday.
Operators at Hong Kong's maritime cargo port, one of the busiest in the world, ceased work late on Saturday, stranding many giant tankers in sea channels not far from shore.
The financial hub is well versed in typhoon preparations and enforces strict building codes, so rarely suffers major loss of life as a result of tropical storms.
But the observatory warned against complacency, saying that Usagi was set to become the strongest storm to hit Hong Kong since 1979 when typhoon Hope killed a dozen people and injured 260.
Usagi was located about 370 kilometres east of Hong Kong as of 10am (0200 GMT) and was expected to make landfall in the evening. The observatory said a "number eight" storm signal was possible, which would shut down most public transport.
China's National Meteorological Centre issued a "red alert" -- its highest-level warning -- as it forecast gale-force winds and heavy rain.
Sunday was a regular day of business in China but in Xiamen city, on the coast of Fujian province, authorities called off school classes and suspended ferries to Taiwan.
En route to Hong Kong and southern China, Usagi forced the evacuation of some 3,400 people in southern Taiwan, dumped more than 70 centimetres (27 inches) of rain on Hualien city, and forced more than 100 flights to be cancelled to and from the island.
A mudslide hit one hotel in a popular hot-spring resort area of Taiwan's Taitung county late Saturday, shattering windows and damaging some furniture.
"I heard a loud sound and (the mudslide) came through the windows of the restaurant in the back. Our customers were safe but we estimate losses of Tw$1.5 million (1.6 million baht)," a hotel worker told reporters.
Remote villages elsewhere in Pintung county suffered heavy flooding.
"I thought a tsunami was hitting ... I've never encountered this before in my life," said a 60-year-old woman who scrambled to safety with her pet dog.
Nine people were injured in Kinmen, a Taiwan-controlled island off China's Fujian province, after they were hit by falling trees, according to the Central Emergency Operation Centre.
But in the Taiwanese port of Kaohsiung, a giant yellow duck designed by Dutch artist Florentijn Hofman -- which has already proved a huge hit in Hong Kong -- was set to be reflated for public viewing as wind speeds ebbed.
Prior to Taiwan, Usagi brushed the far north of the Philippines where a man and a woman drowned when their boat capsized in high seas. Another two people are missing from the mishap.
Authorities in the Batan and Babuyan island groups, which are populated by about 33,000 people, reported toppled power pylons as well as houses, schools and government buildings losing their roofs to Usagi's high winds.
"Some roads are impassable due to debris, landslides and flooding. Local disaster officials told us this was the strongest typhoon they had experienced in years," regional civil defence officer Ronald Villa said.
The region is regularly pummelled by tropical storms. Typhoon Bopha left a trail of destruction in the southern Philippines last year, triggering floods and landslides that left more than 1,800 dead and missing and displaced nearly one million people.
In August 2009, Typhoon Morakot killed about 600 people in Taiwan, most of them buried in huge landslides in the south, in one of the worst natural disasters to hit the island in recent years.