What does the frequently flat base of a cumulus cloud indicate observationally?

Answer

The uniform altitude where lifting air parcels reached saturation simultaneously

The flat base marks the specific elevation where the rising air cooled enough to consistently cross the local dew point boundary, triggering condensation at that uniform level.

What does the frequently flat base of a cumulus cloud indicate observationally?

#Videos

NASA Spotlite: What are clouds made of? - YouTube

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