Stratus cloud

Stratus clouds are low-levelclouds characterized by horizontal layering with a uniform base, as opposed to convective or cumuliform clouds formed by rising thermals. The term describes flat, hazy, featureless clouds at low altitudes varying in color from dark gray to nearly white. The word stratus is derived from the prefix Strato- meaning 'layer'. Stratus clouds may produce a light drizzle or a small amount of snow. These clouds are essentially above-ground fog formed either through the lifting of morning fog or through cold air moving at low altitudes. Some call these clouds "high fog" for their fog-like form.