BIGG1 demonstrated a relation between summer ice nucleus concentration and lunar phase. If one assumes that increase of ice nuclei causes increase in precipitation, relations between precipitation and lunar phase can be accounted for. The effect is global and it occurs in lower latitudes with a delay of a few days. When Bigg's curves are reduced to 34° S. latitude, they show two equal maxima of ice nuclei concentration, the first occurring 6 days, the second 18 days after new Moon. The maxima are 12 days apart (synodic month = 29.53 days).