Hailstones are created when the updrafts in thunderstorms carry raindrops upwards into extremely cold areas of the atmosphere and they freeze. The hailstone can grow by colliding with super-cooled water droplets in the updraft that freeze upon contact with the hailstone. When the hail stone grows too heavy for the updraft to sustain its upward trajectory, it falls to the earth’s surface.
If you cut a hailstone in half you may see the concentric circles or hail rings that are formed, much like that of tree. Therefore the larger the hailstone, the more ice layers or rings it will contain.
An Australian Building Code report from 2010 title “An Investigation of Possible Building Code of Australia (BCA) Adaptation Measures for Climate Change” stated that across 2100 recorded events at that time 44% of hailstorms had hail 2-4cm in diameter, 37% with 4-6cm and just 10% of storms had hail 6-14cm.
Smaller hail tends to appear more uniform in appearance than larger hail that can have jaggered edges. This is caused bu the super-cooled water drops freezing to different parts of the hail and as it grows some areas grow faster and more dramatic than others.
As if big hail isn’t bad enough – it can also have edges!
Image credit: www.weather.com / Carissa Everett shared with Hunter Weather