It is common to have big snowflakes sized around centimeters , but in January 28th there was nothing common in the size of snowflakes flying in the air in army base of Fort Keogh, Montana, US. During the day the snowflakes had been exceptionally big, but this one was a true giant. The soldiers guarding Fort Keogh witnessed very bizarre sight when the most massive snowflake ever fell from the sky.
The flake was sized 38 centimetres and was 20 centimetres thick, meaning the snowflake falling from the sky was size of a dinner plate. In Finland kids like to play and try to catch the flakes with their tongues, with a snowflake this size it would be quite a dangerous game. According to scientific theories, these giant snowflakes can in fact be formed easily. They are formed when a heavy, wet snow is falling with little wind. Under those conditions, flakes that have a slight surface sheen of water easily stick together and form larger flakes.
So this giant flake of Fort Keogh was formed of many small snowflakes. Is that even possible? Standlin, Dubuque, Iowa. A snowflake that large stretches the bounds of credibility. Guinness World Records lists a snowflake 15 inches in diameter and 8 inches thick as measured at Fort Keogh, Montana, in , as the largest.
Large snowflakes consist of "packets" of many smaller snow crystals loosely clinging together. As they fall through the air, individual snow crystals brush past each other, matting together to form larger snowflakes whose fall speeds increase, thereby accelerating the gathering process. As these ice crystals fall and swirl through the clouds that formed them, they form larger flakes by continuing to grow, clumping together, gathering freezing water droplets, or all of the above.
Water droplets that freeze on contact with an ice crystal create tiny snowball particles. And when multiple snow crystals clump together into a jumble, the snow particles they form are known in meteorological circles as aggregates. The largest falling aggregate snowflakes Yuter has photographed have been about 1. The jumble of crystals that make up an aggregate snowflake tend to be only loosely connected, and the overall structure is consequently very fragile.
Wind or other air turbulence can easily break the delicate aggregate into smaller pieces on its way to the ground. That means that the record-setting flake of — the one that was considerably larger than a football — would have needed to fall in very calm wind, or no wind at all.
In addition, the moisture in the air would have needed to be quite high, to allow the flake to gather a plethora of ice crystals and frozen water droplets on its journey down to the ground. That enormous snowflake would also have looked very different from the ones we usually imagine. There is no photographic evidence for the giant flake, but Yuter says that if it existed, it was probably a variation of what she has observed in her own work: a very lumpy aggregate.
It might be tempting to envision a perfectly symmetrical giant snowflake, but the reality is much more interesting. Much more likely is that it was a jumble of crystals together. Please do not cancle the exams on Monday! As a international student, I really wanna to go home!
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