The Shanghai Municipal Flood Control Headquarters urged related departments to take careful flood prevention and control measures.
Shanghai will see more rainfall than usual and be affected by two or three typhoons during the coming flood season, the headquarters warned.
Bad weather such as cyclones and hailstorms are also forecast for the area by the city's observatory.
According to the headquarters, problems still remain in the city's flood control facilities, such as weak flood-control dykes, old and inefficient water pumping systems, and silted riverbeds.