There were 30 tropical cyclones in the western Pacific Ocean in 1931, including 19 typhoons, as well as one that developed in December of the previous year. The most significant typhoon was one that struck eastern China near Shanghai in the midst of the country's worst floods on record; heavy rainfall caused levees to collapse along the Grand Canal, killing an estimated 300,000 people, including about 2,000 people overnight in the city of Gaoyou.