All liquid and solid water particles that fall from clouds and reach the ground, including drizzle, rain, snow, ice crystals, and hail. The essential difference between a precipitation particle and a cloud particle is size; an average raindrop has a mass equivalent to that of about one million cloud droplets. Precipitation elements (ice crystals or droplets that form around soluble particles such as salt) form directly from the vapour state and get larger through collision and coalescence. Eventually they become large enough to respond to gravity, and they fall to the ground.
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