Mobile phone alerts warning of waves of more than 6m were issued to coastal towns, while total rainfall of nearly 1m was expected in northern mountain areas, including the hills near the capital Taipei.
Champi is expected to be at its closest to Taiwan late on Friday, off its northeastern coast, before heading north in the direction of the seas off Shanghai.
Taiwan’s transport ministry said 125 flights had been cancelled on Thursday, mostly domestic ones, though the rail network was so far unaffected. The interior ministry said no evacuations of residents had yet been reported.
Taiwan is generally very well prepared for typhoons, which keeps casualties low.
The typhoon is forecast to first pass over Japan’s westernmost inhabited island, Yonaguni, in Okinawa Prefecture.
In Japan, major carriers Japan Airlines, ANA and Skymark have cancelled more than 100 flights, mostly domestic, between Thursday and Sunday, disrupting travel for over 11,000 passengers.
