I have calculated the mass of the storm cloud for Hurricane Sandy (year 2012, in the United States of America). The dimensions of Hurricane Sandy of 1800 km in diameter and 13 km in height. Considering the density of the storm cloud multiplied by its volume. However the rain that I drop is much smaller than the rain that I would expect to spill over the territory hit by the storm. The mass, which I get for Hurricane Sandy (2012 U.S.A.) is 3.25x10^4 kg/m^2 . I would appreciate the help that would allow me an approach to solve my problem.