Precipitation composed of white or translucent ice crystals, chiefly in complex branch hexagonal form and often agglomerated into snowflakes. For weather-observing purposes, the intensity of snow is characterized as 1) light when the visibility is 1 km (5/8 statute mile) or more; 2) moderate when the visibility is less than 1 km (5/8 statute mile) but not more than 1/2 km (5/16 statute mile); and 3) heavy when the visibility is less than 1/2 km (5/16 statute mile).