Snow is a form of precipitation within the Earth's atmosphere in the form of crystalline water ice, consisting of a multitude of snowflakes that fall from clouds. Snow has an open and therefore soft structure, unless packed by external pressure. See how I have formed these snowflakes into a denser material.
Snowfall tends to form within regions of upward motion of air around low-pressure systems. As we are atop Mount Wellington, it is highly probable that this snow has been formed through an upslope flow of warmer air (containing water evaporation from the ocean) that has been maximised within the windward sides of the terrain at elevation, which has then hit the far colder atmosphere at altitude.
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