Typhoon Podul hit Taiwan's sparsely populated southeast coast on Wednesday packing winds of up to 191 kph, as a large swathe of southern and eastern parts of the island shut down and hundreds of flights were cancelled.
Taiwan is regularly hit by typhoons, generally along its mountainous east coast facing the Pacific.
Podul slammed into the southeastern city of Taitung around 1 pm (0500GMT), Taiwan's Central Weather Administration said.
"Destructive winds from typhoon expected. Take shelter ASAP," read a text message alert issued to cellphone users in parts of Taitung early on Wednesday. The alert warned people of gusts above 150 kph in the coming hours.
Nine cities and counties announced the suspension of work and school for Wednesday, including the southern metropolises of Kaohsiung and Tainan. In the capital Taipei, home to Taiwan's financial markets, there were blustery winds but no impact.
Authorities are also working to evacuate those whose homes were damaged by a July typhoon that brought record winds and damaged the electricity grid in a rare direct hit to Taiwan's west coast.
The government said more than 5,500 people had been evacuated ahead of the typhoon's arrival.
All domestic flights were cancelled on Wednesday - 252 in total - while 129 international ones were axed too, the transport ministry said.
Taiwan's two main international carriers China Airlines and EVA Air said their cancellations were focused on routes out of Kaohsiung, with some flights from the island's main international airport at Taoyuan stopped as well.
After making landfall, the storm is expected to hit Taiwan's much more densely populated western coast before heading for China's southern province of Fujian later this week.
As much as 600 mm of rain was forecast in southern mountainous areas over the next few days, the Central Weather Administration said.
More than a year's rainfall fell in a single week this month in some southern areas, unleashing widespread landslides and flooding, with four deaths.

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