Taiwan cancelled flights and closed schools in parts of its southern region on Wednesday ahead of Typhoon Koinu's expected landfall, the second major storm to make a direct hit on the island in a month.

Taiwan experiences frequent tropical storms from May to November but last month's Typhoon Haikui was the first to slam into it in four years -- unleashing torrential rains, high winds and forcing nearly 8,000 people to evacuate from their homes.

Experts say climate change has made the paths of tropical storms harder to forecast while increasing their intensity, which leads to more rains and flash floods.

Ahead of Thursday's expected typhoon, more than 100 international and domestic flights have been cancelled, while ferry services to Taiwan's outlying islands have also been halted.

More than 200 people were evacuated for fear of landslides in the south of the island, and waves lashing the coast could reach up to seven metres (22 feet) high, authorities said.

Fishing boats were crammed into a fishing harbour in Pingtung county on Wednesday to shelter ahead of the typhoon, while primary schools in the agricultural region of Taitung allowed children to go home early.

"It's barely a month, and we have another typhoon," 65-year-old Yang Pi-cheng lamented to AFP, as she waited to pick up her grandchildren from Dawang Primary School.

A major highway along the coast has also been closed as a precaution.

Koinu -- which has been charting a jagged course for Taiwan's southern tip -- is currently just 200 kilometres (125 miles) east of the island, moving towards it at 10 kilometres per hour.

The typhoon has already brought heavy rains to the mountainous northeast regions of Yilan and New Taipei City.

"We forecast that its centre will pass through the Hengchun Peninsula at the southern tip of Taiwan tomorrow morning," said Lu Kuo-chen, head of Taiwan's Central Weather Administration.

After making landfall in Taiwan, Typhoon Koinu is forecast to move towards the eastern coast of China's Guangdong province, said the weather observatory in nearby Hong Kong.

The Chinese territory -- which last month was skirted by another typhoon before being flooded by the heaviest rainfall in 140 years days later -- will issue its lowest typhoon signal on Wednesday evening.