Nearly everyone is aware that no one has ever observed two snowflakes that are exactly alike regardless of the fact that there are an infinite number of snowflakes in a heavy snowfall. But are there different types of snowflakes? Yes, there are and they are classified as four basic types with many subtypes.
First let’s look at how snowflakes form. All snowflakes start out as single molecules of water vapor inside clouds. The water vapor forms an ice crystal when the temperature drops below freezing and sticks to a tiny particle of dust or bacteria that has become airborne due to wind. As more water molecules stick to the core particle, a clump of ice crystals forms a crystal-like shape, which we call a snowflake. The type and shape of a snowflake is directly affected by atmospheric conditions and ambient temperature at the time the snowflake forms in a cloud.
There are snowflakes that are long, solid and thin like a needle and in fact that is what they are called. Needle snowflakes form when the temperature inside the cloud is around 23 degrees Fahrenheit (-5 degrees Celsius). If you look closely at them, they will look like short white cat hairs.
Another type of snowflake is shaped like a column with cone shapes hollowed out in the ends. These are called column snowflakes and are formed when the temperature inside a cloud is approximately -8 degrees Fahrenheit (-22 degrees Celsius). Sometimes the wind will push these column shaped ice crystals into a different region of the cloud and the different air temperature will cause flat plate-like formations on the ends of the column and these snowflakes are then called capped columns. Sometimes the column section of a capped column is short and almost non-existent; the two flat ends come together to form a shape similar to the classic “flying saucer” shape.
Flat snowflakes that look like a hexagon cut from a piece of paper are called plate snowflakes. Plate snowflakes are formed when the temperature inside the clouds is between 27 and 32 degrees Fahrenheit (0 to -3 degrees Celsius). Some subtypes of a plate-crystal snowflake are stellar plates and sectored plates.
Probably the most common shape of snowflakes is the star cyrstal. This is the one that most people imagine when they hear the word snowflake. Star crystal snowflakes are formed when the temperature inside a cloud is about 5 degrees Fahrenheit (-15 degrees Celsius). They are very delicate and wind can blow them apart or they can be broken simply by colliding with another star crystal, but they can just as easily combine with another snowflake to form a larger snowflake. Star crystal snowflakes are generally six sided and have a lacy appearance. There are several recognized subtypes of star crystal snowflakes such as stellar dendrites and fernlike stellar dendrites.
Of course, any snowflake can start out as one type; however, since it has a long and perilous journey, by the time it reaches the ground it will be a totally different type. The core particle, variations in temperature, wind and the density of the snowfall will make it unrecognizable as the same snowflake that started in the clouds.