Idaho, USA - Curious natural snow formations appeared briefly in the grasslands of southern Idaho. These cylinders of snow, form similar to bales of hay, were not shaped by humans but the result of a natural weather phenomenon rare.
The firefighter Tim Tevebaugh discovered a field full of these cylinders of snow falling from his work. "I had not seen from the morning, they had to be formed within a few hours," said Tevebaugh.
Each cylinder frozen, shaped haystack, was about 60 cm high. The formation of cylinders of snow is an extremely rare natural phenomenon known experts. They are the result of a specific combination of temperature, humidity, wind speed, snow and depend on the type of terrain.
This training can not be created on a flat or gently rolling open, covered with a layer of smooth ice or a crust of snow. The cylinders take their shape when wet snow falls. The air temperature must be maintained at around 0 ° C to 1 ° C and a period of sustained winds of at least 40 km / h is necessary. Succession of gusts of wind will roll the "snowball" newly formed, which collect more and more snow on the move.
Given the precise weather essential, it is easy to understand why people almost never do this. Many professionals do meteorologists have ever seen. Moreover, these cylinders are quite fragile. This phenomenon is sometimes form in the plains of North America where the weather can change suddenly due to meet the masses of cold, dry air from the Arctic to the masses with more hot and humid Gulf of Mexico.