When the temperature is much below freezing, the snowflakes that fall from the sky are significantly smaller in size. This is because the snow crystals are drier, making them less likely to attach to other snow crystals. This sort of snow is powdery and difficult to shape into a snowball.
When the temperature is near or just above freezing, the snowflakes that fall from the sky are larger in size. This is because there are more ice particles within the snowflake that can stick together to form balls or clusters.
Snow crystals grow during a storm when temperatures stay below 32 degrees F. But once the temperature rises above 32 degrees F, the growth stops until the next storm comes through. When it gets warmer out than expected, some large crystals may form after all.
The diameter of a snowflake is about 1/100th of an inch for every degree below zero Fahrenheit. For example, if the temperature at which you find yourself is -20 degrees F, then the snowflakes that are falling around you are about 0.6 microns wide.
At +20 degrees F, snowflake diameters range from 1.4 to 3.0 microns.
A micron is one millionth of a meter; so 0.6 microns = 60 nanometers, or 6 billionths of a meter. That's tiny!
The size discrepancy is due to how frigid the temperatures are when it snows. Individual snow crystals are microscopic, but when they adhere together, they form considerably bigger snowflakes, as shown in the video above. As the temperature rises, so too do the flake sizes.
There are many factors that go into how big or small a snowflake is. The lower the humidity, the smaller the flakes will be. Snow that falls on very cold ground may not even have water droplets inside it, which means there are no nuclei for the crystals to grow around. Instead, snowflakes form when gusts of wind blow across the surface of the ice particles. This causes them to break up and scatter away from each other, forming new crystals that can get larger than any others nearby.
Snowflakes are almost perfect spheres, but some are pointed one way and some another. The more pointed a crystal is, the faster it will melt when you hit it with your face. This is why people sometimes get cut up by falling snow: The crystals break off the storm cloud and attack anyone who comes into contact with them.
People have been making observations about snowflakes for hundreds of years. In 1712, English scientist Charles Linnaeus published his book "Systema Naturae," which included a chapter on snowflakes.
Snowflakes come in a variety of forms and sizes. When snow crystals descend, they collide with other snow crystals, causing them to expand in size and appear as bigger snowflakes as they approach the earth. Light breezes also aid in the development of bigger snowflakes, which can be broken up as they descend in stronger gusts. The more water that is present during formation, the larger the crystal will be.
The term "snowflake" was originally used to describe patterns formed by rain or snow. However, it has since become known as one of nature's beautiful symbols. Snowflakes have three main parts: a head, a stem/leavel, and some form of terminal. The surface of a snowflake is made up of very small ice particles called crystallites. Each crystallite has its own flat surface that is either smooth or has bumps or pits on it. This accounts for the various shapes of snowflakes.
The most common type of snowflake is the perfect hexagon. It is made when six identical faces are formed at each stage of the freezing process. Then, as more ice crystals develop, these six faces often continue to branch out into more sides. This results in a pattern of regular polygons being formed. Some examples of this type of snowflake include the Icosahedron, Dodecahedron, and Tetrahedron.
Another common type of snowflake is the branched star.
Snowflakes occur in clouds as the temperature falls below zero degrees Fahrenheit (0 oC, or 32 oF). The ice crystals grow around microscopic particles of dirt transported into the sky by the wind. As they fall through the cloud layer, these crystals merge together to form larger and larger structures until they reach the ground.
The average temperature for snow to form flakes is about -15 degrees F (-26 degrees C). But temperatures as low as -45 degrees F have been recorded in the mountains of Canada. And even lower temperatures have been measured inside glaciers when air bubbles are trapped beneath the surface of the ice.
As soon as water drops freeze, they begin to grow crystals. Because there is more space between the frozen grains of water than there is within it, the ice becomes porous. This makes it less dense than liquid water, which is why objects such as float in liquid water. When the temperature drops below 0 degrees C (32 degrees F), liquid water turns into a solid called "snow".
A snowflake is formed when moisture in the air is cold enough so that it changes from a liquid to a gas. The gas then tries to escape through any opening it can find. Since each crystal is a point source of moisture, the first thing that happens is that they attract each other like magnets.
Generally, the smaller the crystals get as the temperature drops. As the crystals fall from the frigid clouds, they collide with other crystals and freeze together, forming new forms. This is one of the reasons why it is so difficult to produce two snowflakes that are precisely same. There are just too many variables that can affect how a crystal forms.
The difference is also seen in the fact that when it is very cold, the snowflakes do not all look like stars. Some of them have six or seven points, while others have only four or five. Also, some are wider at the base than others.
It takes several hundred thousand snowflakes to make an average-size snowball! So, not only are snowflakes beautiful, but they're also useful for counting votes in elections etc.