China's meteorological authority on Thursday evening issued an orange alert, the second highest of the four-tier warning system, for storms across southern and eastern regions.
It is the first time that the National Meteorological Center has issued an orange alert for rainstorms this year. In June, storms in the south and a tornado in eastern Jiangsu Province killed more than 100 people.
Over the next four days, parts of Jiangsu, Anhui, Henan, Hubei and Hunan will be hit by torrential rain, the center said in a statement.
Rainfall is expected to reach up to 400 millimeters in these areas, coupled with gales or thunderstorms.
The center advised people living in the affected areas to take precautions against possible landslides and mud-rock flows while those living in mountainous areas should move to safe places in advance.
Local governments along the Huaihe River should prepare for possible floods, the center cautioned.
China has a four-tier color-coded warning system for severe weather, with red being the most serious, followed by orange, yellow and blue.