Richard Hammond explores the weather conditions that form hail.
The two variables are summer thermals and powerful thunderstorms. As thunderclouds are very high, the water droplets contained within them freeze.
The upward thermals keep the ice supported in the cloud where new super cooled water enlarges the ice until they are too heavy for the up-drafts to be supported. This is when they fall to the ground.
Teacher Notes
This short film provides a description of the conditions needed for hail formation and an explanation of how hail forms. Your class could investigate other atmospheric conditions that produce hail.
Curriculum Notes
This topic appears in geography and physics at KS3 and KS4 in England, Wales and Northern Ireland and National 5 in Scotland. At GCSE it appears in AQA, OCR A, EDEXCEL, EDUQAS, WJEC and CCEA, in SQA at National 5.
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