Taiwan is regularly hit by typhoons, generally along its mountainous, sparsely populated east coast facing the Pacific.
The mid-strength Typhoon Podul, packing wind gusts as strong as 191km/h, was heading for the southeastern city of Taitung as it intensifies and was expected to make landfall nearby later on Wednesday, weather officials said.
"Destructive winds from typhoon expected. Take shelter as soon as possible," read a text message alert issued to cellphone users in parts of Taitung early on Wednesday. The alert warned people of gusts above 150km/h 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 was 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 5500 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 in 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 600mm 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.
with EFE
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