The authorities in Shanghai, Zhejiang and Fujian province ordered 2 million people evacuated from ships and coastal regions.
Matches for the women's World Cup in Shanghai were rescheduled and moved and numerous flights out of Shanghai and other regional airports were cancelled.
With wind gusts of up to 260kph, meteorological officials said Wipha would be the most destructive storm to hit the Shanghai area in years if it followed a course northward that would take it just west of the city.
The deadliest storm to hit the China coast in recent years was Typhoon Winnie in 1997, which killed 236 people.
On Tuesday, one worker was reported killed and another seriously injured as the fringe of Wipha lashed Taiwan, knocking down scaffolding at a highway construction site in Taipei, Taiwan's Disaster Relief Centre reported.