Lake Ice and 
Snow Science 

SNOW: Snowflake Formation

CONDITIONS LEADING TO VARIOUS SNOWFLAKE SHAPES

Note that this diagram has a different supersaturated scale than the one on the previous page (% versus g/m³). This produces a straight water saturation line rather than a curved one.

NEW SNOW CRYSTAL CLASSIFICATION

MORPHOLOGICAL CLASSIFICATION				PLACE OF FORMATION	PHYSICAL PROCESSES
Basic Classification	Subclass		Shape
Precipitaton particles	Columns		Short prismatic crystal, solid or hollow	Clouds	Growth at high supersaturation at -3°C to -8°C and below -22°C
	Needles		Needle-like, approx. cylindrical	Clouds	Growth at high supersaturation at -3°C to -5°C
	Plates		Plate-like, mostly hexagonal	Clouds	Growth at high supersaturation at 0°C to -3°C and -8°C to-25°C
	Stellars, Dendrites		Six-fold star-like, planar or special	Clouds	Growth at high supersaturation at -12°C to-16°C
More images of snow crystals			Electron microscope images of snowflakes

For a complete description of snow cover properties click here.