Definition of reservoir. 1 : a place where something is kept in store: such asa : an artificial lake where water is collected and kept in quantity for useb : a part of an apparatus in which a liquid is heldc : supply, store a large reservoir of educated people.
Four types of winter precipitation. While all forms of precipitation start as snow high up in the clouds, there are four primary types that eventually reach the ground: snow, sleet, freezing rain and plain ol' rain. Snow occurs when the atmosphere is cold all the way from the clouds to down here at the surface.
Snow requires a temperature below freezing almost all the way through the atmosphere (it can still snow if the surface temperature is a little above freezing). Sleet occurs when the temperature of the lower level of the atmosphere is below freezing, and that layer is thick enough to allo liquid water to freeze (if not thick enough, then freezing rain is the result). Hail falls from thunderstorm where water freezes up in the storms, and the stones fall to the ground before melting.