The storm cut power to more than 49,000 households across Taiwan, although supply has since been restored to most.
“Typhoon Doksuri should not be underestimated,” Chen Chi-mai, mayor of the southern port city of Kaohsiung, said on Facebook late on Wednesday.
Taiwan’s armed forces pressed ahead with a large-scale anti-landing drill on a beach near Taipei Port just outside the capital, simulating the repulsion of an enemy force with ground troops and tanks amid high military tensions with neighbouring China.
The storm has disrupted parts of Taiwan’s main annual Han Kuang exercises and air-raid drills that started on Monday. Authorities cancelled some exercises citing safety concerns and the need to make preparations for the typhoon.
Doksuri is expected to make landfall in China on Friday morning somewhere between Dongshan and Putian in the southeastern province of Fujian.
On Thursday, three coastal cities in Fujian shut schools, businesses and factories, while flood control authorities in one of them, Xiamen, warned of a “serious impact”.