What is the difference between rain and drizzle?
NARRATION: The average raindrop is about two millimetres across. But when it drizzles, they鈥檙e as little as half a millimetre. So how can you see that difference with the naked eye?
Look closely at a puddle鈥檚 surface. If the drops are splashing - like here - then it is rain. But if there are no splashes, then it only qualifies as drizzle. Officially.
Clever, isn鈥檛 it? Splashes - rain. No splashes - drizzle.
Richard Hammond demonstrates a visual technique to distinguish between drizzle and rain.
Official measurements state that drizzle measures at 0.5 millimetres compared to rain droplets, which measure two millimetres on average. A puddle surface is used to distinguish visually between the two.
If there are visible splashes, then rain is falling. If there are no splashes visible to the naked eye on the surface of the puddle, drizzle is falling.
Teacher Notes
Ask your students to use the distinction between rain and drizzle outlined in this short film to inform a weather diary.
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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