A
stratus cloud (St) is a
cloud belonging to a class characterized by horizontal layering with a uniform base, as opposed to convective clouds that are as tall or taller than wide (these are termed
cumulus clouds). More specifically, the term stratus is used to describe flat, featureless clouds of low altitude varying in color from dark gray to nearly white. These clouds are essentially fog that is above ground level and are formed either through the lifting of morning fog or when cold air moves at low altitudes over a region. These clouds do not usually bring
precipitation, although drizzle may occur.
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