Why are some clouds flat underneath? © Getty Images

Why are some clouds flat underneath?

Floating along without a care, one has to wonder about the clouds flat bottoms.

Asked by: Charlie Mack, Uckfield


As warm air rises, the water vapour remains invisible until the air cools enough for it to condense into water droplets. The altitude where that happens marks the bottom of the cloud. Providing that more air feeds in from below, new cloud will form there and preserve the flat bottom. The existing cloud is pushed upwards, forming a fluffy top.

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