At least one person was killed as Typhoon Doksuri lashed the northern Philippines with strong winds and rain on Wednesday.
Rivers overflowed and thousands were left without power as the storm made landfall.
Coastal communities had been evacuated ahead of the storm, which brought winds of up to 175kph and is expected to sustain strength as it continues its course towards Taiwan and China.
One person was killed in the province of Rizal. More than 4,000 passengers were stranded at various ports in the country after sea travel was suspended, the Philippine coastguard said.
“We are being battered here,” Manual Mamba, governor of northern Cagayan province told Reuters.
The Philippine weather bureau said the storm was expected to cross the Taiwan Strait and make landfall in China's Fujian province on Friday morning.
Authorities in Taiwan issued warnings for several counties and cities in the island's south, including the major port city of Kaohsiung.
More than 300 people have been evacuated in southern and eastern Taiwan as a precaution with Doksuri forecast to bring up to 1 metre of rainfall].
The storm forced the cancellation of dozens of flights as well as many ferry services. Railway services between eastern and southern Taiwan were to be suspended.
On Wednesday, China's National Meteorological Centre upgraded its typhoon alert to red from orange, the highest level in the colour-coded warning system.
Doksuri is expected to move north-west at a speed of 10kph to 15kph and enter the north-eastern part of the South China Sea from Wednesday night until Thursday morning, China's Central Meteorological Administration said.
It will sweep past southern Taiwan on Thursday and is predicted to make landfall along the coasts of central Fujian and eastern Guangdong provinces on Friday morning, Chinese weather forecasters predicted.
The Guangzhou Daily reported that it could be the strongest typhoon that has landed or seriously affected eastern Guangdong in the past 10 years.
China upgraded its emergency response to Level II from Level III and the Central Meteorological Administration urged people to stock food, necessities and candles as a precautionary measure.
A Level II emergency response warns an oncoming typhoon could severely affect the country, according to the State Council's national emergency plan for flood control and drought relief.
Doksuri would be the second typhoon to make landfall in China in less than two weeks after Talim, in Guangdong province, on July 17.
