How does snow form?
Snow crystals form in clouds when the temperature is below freezing. They are made by water droplets freezing onto ice particles. As an ice crystal falls through the cloud it bumps into others and becomes a snowflake. This processing of bumping into others, along with some melting and re-freezing helps to form their complex design. The air that the snowflake falls through has to be below freezing otherwise the snowflake will melt and turn to rain.
What do snowflakes look like?
Snowflakes are always six sided and it is thought that no two are ever the same. The shape and form of a snowflake depends on the temperature and amount of moisture within the cloud. Snowflakes can be divided into six main shapes, plate (flat), stars, column, needle, dendrite (lacy) and capped column. When it is very cold the snow is very fine and powdery and the snowflakes are quite simple in design, normally rod or needle shaped. When the temperature is closer to freezing point (0 degrees Celsius), the snowflakes are much larger and more complex in design, such as a star.
The Snowflake Man
An American photographer called Wilson A Bentley spent much of his life looking at snowflakes and taking pictures of them. He developed a huge collection of several thousand photographs of snowflakes and was nicknamed ‘The Snowflake Man’. In 1925 he was quoted as saying: “Under the microscope, I found that snowflakes were miracles of beauty; and it seemed a shame that this beauty should not be seen and appreciated by others. Every crystal was a masterpiece of design and no one design was ever repeated. When a snowflake melted, that design was forever lost.”
It is recorded in the Guinness Book of World Records, that the world’s largest snowflake was 38 cm wide and 20 cm thick. This occurred at Fort Keogh, Montana, USA on 28 January 1887.
The tallest snowman ever made measured 34.63 metres and was made by residents of Bethel, Maine, USA. It took 14 days to build, finally being completed on 17 February 1999. Nicknamed Angus, he had vehicle tyres for his mouth and trees for arms.
Why not make your own pretty snowflakes.
Follow the instructions below. You might need a adult to help you with the cutting out.
1) Take a large square piece of white paper and fold it in half to make a triangle.
2) Fold your triangle in half again, corner to corner, to make a smaller triangle.
3) + 4) Your triangle now needs to be folded in to three. Fold the two sides across each other, making sure both sides are equal. It should look like diagram 4.
5) Cut straight across the bottom of the paper to make a triangle with a straight base like the one below.
6) Now you can make random cuts to make your own snowflake pattern.
Web page reproduced with the kind permission of the Met Office