Meteorology (Weather)/Hail size

Advertisement


Question
What determines the size of hail?

Answer
Hi Amanda

Hail forms in thunderstorms. Thunderstorms have extreme up and down air drafts. A hail stone starts out as a falling rain drop that gets caught in an updraft that takes the rain drop to a high altitude (height) that is above the freezing level (below 32 degrees Fahrenheit); the rain drop freezes into a ice drop (so to speak) which then begins to fall as a small hailstone which then goes into a repeat process of up and down with each trip an additional coating of water that the freezes creating an additional coating of ice. When the piece of hail get too heavy for the strength of the up-draft it then falls to earth as a hail stone. You can tell how many up/down cycles were made by a particular stone by cutting it in half and counting the coating striations- it has a structure very similar to an onion.

For more info, see:

http://stormhighway.com/blog2012/june2612a.php

https://www.ucar.edu/communications/factsheets/Hail.html

http://weatherknowledge.com/learn.html  

Meteorology (Weather)

All Answers


Answers by Expert:


Ask Experts

Volunteer


Donald Rosenfeld

Expertise

Any questions (except private) answered from the 1st grade level on up pertaining to any aspect of Weather. I am a 20 year member of the American Meteorological society and a long time forecaster of eastern United States snow storms and Hurricanes.

©2016 About.com. All rights reserved.