The typhoon stayed just offshore until about 6pm Sunday, when it made landfall in a coastal area of Taishan city in China's Guangdong province, China's National Meteorological Center said.Â
It then weakened to a severe tropical storm with maximum sustained winds of 108km/h.
Weather authorities in Hong Kong had lowered the typhoon signal in the Asian financial hub on Sunday afternoon - to eight from the maximum of 10 - after more than 110mm of rain fell within three hours.
Much of the rain concentrated on the northern region neighbouring the mainland, the city's observatory said, warning of more to come.
The eye of the storm passed just south of Hong Kong about midday with maximum sustained winds of 140km/h, the observatory said.
The high winds brought down trees in Zhuhai and other cities on China's southern coast.
In Hong Kong, vehicles weaved around branches strewn on the streets.
The government said in a statement 26 people sought treatment in public hospitals, while 253 flocked to its shelters, and 471 fallen trees were reported.
In North Point near the city's harbour, large swathes of scaffolding were swept off a residential building and onto the road.
Authorities in neighbouring Macau, the world's biggest gambling hub, also downgraded the typhoon signal to eight from 10, warning of flooding in its inner harbour area and urging residents to stay safe, public broadcaster TDM said.
Hong Kong's airport authority said 80,000 travellers were hit by the rescheduling of 400 flights forced by the typhoon.
Cathay Pacific Airways cancelled all flights from Hong Kong airport on Sunday, waiving ticket change fees and arranging for rebooking.
Most public transport in Hong Kong was suspended, including ferries, amid high sea swells.
