What temperature is needed for the formation of snowflakes?

See how much water vapor; There is a lot of water vapor, and it will snow around 0 degrees; There is less water vapor, and there will probably be-10 degrees.

There are two conditions for the formation of snowfall:

One condition is that water vapor is saturated. Another condition is that there must be condensation nuclei in the air.

The size of snowflake crystals is closely related to the temperature at which water vapor condenses and crystallizes. The colder the weather, the lower the temperature and the smaller the snowflake crystal. When the weather is very cold, the diameter of snowflake crystals formed is often less than 0.05 mm. Meteorologists have observed that prismatic ice crystals will form when the temperature is between -8℃ and -5℃.

When the temperature is -5℃ to -3℃, needle-like ice crystals are formed; When the temperature is -3℃ to 0℃, thin hexagonal plate-like ice crystals are formed. It can be seen that when the temperature is -3℃ to 0℃, the shape of snowflake is the largest and most complete. Snowflake crystals formed in very cold weather are so small that they are almost invisible to the naked eye. Only when they shine in the sun can people find them as fine powder. This kind of snow is called dry snow.

Extended data:

Historical stories about snow

1, Su Wu has tasted ice and snow.

Su Wu sent a mission to Xiongnu, so he detained Su Wu because his subordinates rebelled and angered Khan. Khan wants to accept Su Wu, but Su Wu is very loyal. Khan locks him in the cellar and won't let him eat or drink. So Sun Wu ate snow felt wool, and later Su Wu was banished to Beihai to graze. Su Wu was indomitable in Xiongnu 19 and became a well-known national hero.

2. Chengmen Sydney

In the Northern Song Dynasty, Shi Yang and his friends went to Cheng Yi to study. When he arrived, it happened that the meter was sleeping. When he saw the half-open door, Shi Yang didn't go in directly, but waited outside. It was snowing heavily, and it was always cold outside in Shi Yang. Finally, Cheng Yi was very moved. Teach him well. Shi Yang didn't live up to his high hopes, and the story has been widely circulated ever since. Tell us to respect the teacher and respect the road.

3. Sun Kang Xue Ying

It is said that a scholar named Sun Kang studied very hard. His family is poor, but he loves learning very much. But he didn't have the money to buy an oil lamp. He felt that he had wasted a lot of time. Later, he found that the snowy night was very bright, so he took a book and read by the night light reflected by the snow.

When it is cold, he goes running to keep warm. It is his efforts that make him an example of the world bachelor and tell us to study hard.

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