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Hailstone sizes

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Hail stones are raindrops that have been pushed up into the colder atmosphere by an updraft and frozen. These tiny hailstones can collide with supercooled water, growing in size. Once they are too heavy, they will fall as hail.

Most often, they are small, but once in a while, they can become scarily large. This is when they can damage your car, crops or weather station. Or you if your are caught out in it.

Believe it or not, there is an official size chart for classifying your hail:

Description Size in cm
Pea 0.5-0.9
Mothball 1.0-1.5
Marble, grape 1.6-2.0
Walnut 2.1-3.0
Pigeon egg to golf ball 3.1-4.0
Pullet egg 4.1-5.0
Hen egg 5.1-6.0
Tennis ball to cricket ball 6.1-7.5
Large orange to softball 7.6-9.0
Grapefruit 9.1-10.0
Melon >10.0

Sadly, your weather station cannot measure these.

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