A nucleation nozzle for forming freezing nuclei for devices for making artificial snow, starting from a jet of pressurised liquid, comprising a compressed air duct having an inlet opening and an outlet opening. A first stretch of the compressed air duct has a cross section which decreases in the flow direction of the compressed air, from the inlet opening to the outlet opening. The first stretch is followed by a second stretch having a cross section which increases in the flow direction of the compressed air from the inlet opening to the outlet opening. There is provided at least one water duct having an inlet opening and an outlet opening. The water duct is separate from the compressed air duct. The outlet opening of the water duct is positioned close to the outlet opening of the compressed air duct.