At least 22 people have been killed and more than a million forced from their homes as Typhoon Lekima hit China, according to state media.
Officials said the deaths were caused by a landslide triggered by the storm. Ten others have been reported missing.
Lekima made landfall in the early hours of Saturday in Wenling, between Taiwan and China's financial capital Shanghai.
The storm was initially designated a "super typhoon", but weakened slightly before landfall.
The fatal landslide happened in Wenzhou, near where the storm made landfall, state media said. It occurred after a barrier lake - or natural dam - formed, pooling water from the heavy rains before collapsing.
Lekima is now slowly winding its way north through the Zhejiang province, and is expected to hit Shanghai, which has a population of more than 20 million.
Emergency crews have battled to save stranded motorists from floods and searched for survivors in the rubble of damaged buildings. Fallen trees and power cuts are widespread.
Authorities have cancelled more than 1,000 flights and cancelled train services in preparation for the storm. Shanghai Disneyland was also shut for the day.
The storm is expected to weaken further by the time it reaches the city, but will still bring a high risk of dangerous flooding.
"Now the disaster zones are mainly in the rural-urban integration zones," said Fu Songliang, head of a rescue team for Ningbo City's fire service.
"These are low-lying areas. When the flooding from mountainous areas converges and comes down, these areas are quite seriously affected," he told Reuters news agency.