Raindrop size comparison
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A comparison of precipitation sizes – from tiny cloud droplets to record-breaking hailstones!

Cloud droplets can range in size from 0.001 to up to 0.1 mm but a typical cloud droplet is around one hundredth of a millimetre. Find out more here: https://www.metoffice.gov.uk/learning/clouds

Once cloud droplets become larger than 0.1 mm, they can start falling from the cloud. Tiny drops with a diameter less than 0.5 mm are defined as drizzle. These droplets remain spherical due to surface cohesion.

Larger raindrops, typically when their diameter exceeds 2 mm, become morphed due to air resistance. The bottom of the drop starts to flatten.

Even larger raindrops normally morph further before breaking into two or more smaller droplets. However, the largest observed raindrop was 8.8 mm. This was observed on two separate occasions: in Brazil in September 1995 and in the Marshall Islands in July 1999. It’s thought theoretically possible that some raindrops could be as large as 1 cm
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2004GL020167

Hailstones can come in all shapes and sizes. From pea-sized to grapefruit-sized – or larger. The larger the hailstones, the greater the risk of damage from a hailstorm. Damaging hail can and does occur in the UK, especially in the summer. However, it’s in the USA where severe thunderstorms with damaging hail are more common. According to the US National Weather Service, severe hail is defined when hail is larger than a quarter / one inch / 25 mm and the risk of damage increases.
https://www.spc.noaa.gov/faq/tornado/hailjim.htm

The largest hailstone on record – in terms of diameter – was measured in Vivian, South Dakota on 23rd July, 2010. This hailstone measure 20 cm or 8 inches in diameter.
https://www.webcitation.org/5rhd1coDR?url=http://www.crh.noaa.gov/abr/?n=stormdamagetemplate
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