Overcast or overcast weather is the meteorological condition in which clouds obscure 95% or more of the sky. Meteorology (from Greek grc μετέωρος metéōros, "high in the sky" and grc -λογία -logia) is the Interdisciplinary A cloud is a visible mass of droplets or frozen crystals floating in the atmosphere above the surface of the Earth or another Planetary body

Overcast happens when the entire sky becomes covered with clouds; hence the word to describe it, overcast. Sometimes clouds can be different colors such as black or white, but the word usually refers to gray. In extreme cases, it can be impossible to see distinct borders of clouds; the whole sky will be a dull white with no gaps of blue in between.