Atmosphere And Weather

How does Hail Form

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"How does Hail Form"
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Hail is a kind of snowball made by nature.  Humans can also manufacture hail, but when they do, they not only insult nature.  They are also coming up with a counterfeit product that can’t be called hail in the formal sense.

Prior to diving into nature’s recipe for making hail, it would be useful to define it first.  As a class of snowball, hail can be as tiny as salt tablets or as big as golf balls.  Its density can range between hardened white sugar and a naphthalene ball, you know, the kind you put in your closet to repel cockroaches.

While hail can be benign, it may also rip through open umbrellas from time to time.  Hence, it will be wise to stay away from the path of a serious hailstorm by taking shelter under something more durable than fabric.

Anyone who has been hit by hail knows only too well that it can be annoying to mildly painful.  On some occasions, hail may cause some bruising or even some form of bleeding.  That hail can manage to break car windows may be an exaggeration, but certainly not when accompanied by a skilled car thief.

At any rate, nature’s recipe for hail requires the following ingredients:

A thunderstorm with an updraft of about 90 miles per hour or more

Plenty of rainwater

Tall clouds

Strong winds

The updraft is the key ingredient to the perfect hail.  Without it, the thrill of hurting someone is significantly diminished.  An updraft is a current of air that moves upwards towards the clouds.

Alicia Bodine, in her capacity as an eHow contributor explains:  “As the rain begins to fall out of the clouds a large updraft sweeps the rain high up in the cloud.  The cloud is much colder up at the top which causes the up-swept rain to freeze.”

From this point onwards, the law of gravity takes over, bringing down the hail either gently or violently.  Of course, the intensity of the winds prevailing at the time may also add a different flavor to the kind of hail that humans and other living organisms may be the unlucky recipient thereof.

Luckily, a hailstorm doesn’t last very long.  Bodine explains that it is precisely the speed of the thunderstorm, which mitigates the circumstances of a hail shower.  This is why hailstorms typically last a few short minutes.  As a general rule, the faster the thunderstorm, the shorter the suffering caused by the hail.   

In some U.S. states, hail can become a serious threat to livestock or even crops.  A commentary to S. Mithra’s landmark hail dissertation at reveals that the tropical islands of Fiji might have been hit by hail at one time.  It’s not uncommon though for a hail shower to hit Melbourne, Australia during the winter months.

Just as storms have eyes, a hailstone according to S. Mithra, “begins to form as an ice nucleus, a small cluster of super cooled water droplets or clumps of snow.”

The author further explains that “much larger hailstones can be made when two smaller ones freeze together.”

This is may well be nature’s way of mimicking a little boy, who with his bare hands, can make much bigger, stronger ammunition by compressing snow in his palms, and combining the two.  Or is it the other way around?

In the final analysis, humans big and small can and will be able to make hail artificially.  However, so far only nature can throw it in such a way that it hurts the greater number of people.   

More about this author: Richie Mogwai

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