At least 28 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.
Shanghai evacuated some 250,000 residents, with another 800,000 in Zhejiang province also being taken from their homes.
An estimated 2.7 million homes in the region lost power as power lines toppled in the high winds, Chinese state media said.
Chinese weather forecasters said the storm, which had winds of 187km/h (116mph) when it made landfall, was moving north at 15km/h.
Coming just a day after a magnitude six earthquake, experts warned that the combination of earth movement and heavy rain increased the risk of landslides.
Lekima is one of two typhoons in the western Pacific at the moment.
Further east, Typhoon Krosa is spreading heavy rain across the Northern Mariana Islands and Guam. It is moving north-west and could strike Japan some time next week, forecasters said.