The mass-distribution of raindrops and solid precipitation elements produced by Northwest Monsoon was observed by the photographic method at Shiozawa in midwinter, 1953, and it was found that the distribution of raindrops or small snow particles is exactly reprented by Marshall and Palmer's formula, but that of snow flakes is extremely different from their formula. In the case of the precipitation which included snow flakes, the distritribution of small precipitation elements was smaller than that shown by Marshall and Palmer's formula, but on the contrary that of snow flakes was much larger than that represented by their formula.
And many snow flakes of equivalent diameter larger than 4mm were measured, although raindrops observed in the period were all smaller than 2mm in diameter.
From these results, it was suggested that the snow flakes would split in falling before they melt into raindrops.