More than 2.5 million people in Guangdong province have been affected by the storm, China's official Xinhua News Agency reported Friday.
Nearly 4,000 homes have been destroyed and more than 428,000 acres of farmland flooded, the provincial flood control and drought relief headquarters said.
Rain is expected in the province for the next two days.
Police and firefighters in central China were dispatched to rescue about 100 people trapped by flooding in four villages in Hunan province. Some parts of the province's Lanshan County had received 15.75 inches of rain in the previous 36 hours.
Local government officials described water levels on the Shunshui River as being above safe levels.