Clouds remain suspended because their tiny water droplets or ice crystals fall very slowly while air currents mix and lift them. A cloud can contain a large total mass of water without behaving like one giant falling object.
Tiny droplets change the picture
Most cloud droplets are much smaller than raindrops. Their low terminal speeds allow even modest rising air motions and turbulence to keep them aloft for long periods.
A cloud is not a rigid object
It is a constantly changing collection of droplets and ice in moving air. Some particles settle while others form through condensation or evaporate. Its visible shape can persist even though individual droplets change.
How rain eventually falls
Droplets must grow through collision, coalescence and sometimes ice-related processes. Once precipitation particles become sufficiently large, they can fall faster than the air supports them.
Why clouds often have flat bottoms
Rising air begins forming visible droplets near the level where it cools to saturation. That cloud-base height can be similar across nearby updrafts, creating a relatively level underside.
Frequently asked question
Does gravity stop acting on a cloud?
No. Gravity acts on every droplet; the droplets’ small size and motion of the air explain their suspension.
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