Stratocumulus cloud or less defined layer of clouds. Stratocumulus castellanus may develop into cumulus congestus (and even further into cumulonimbus) under auspicious conditions. Any showers from stratocumulus castellanus are not usually as heavy as those from cumulus congestus. Stratocumulus Opacus is a dark layer of clouds covering entire sky without any break. However, the cloud sheet is not completely uniform, so that separate cloud bases still can be seen. This is the main precipitating type, however any rain is usually light. If the cloud layer becomes grayer to the point when individual clouds can’t be distinguished, stratocumulus turn into stratus clouds. Stratocumulus
Sheet (sailing) flat, thin surface, such as a sheet of paper or a bed sheet. In nautical usage the term "sheet" is applied to a rope or chain attached to the lower corners of a sail for the purpose of extension or change of direction. The connexion in derivation with "shoot" is more clearly seen in "sheet-anchor", one that is kept in reserve, to be "shot" in case of emergency. Fore-and-aft rigs comprise the vast majority of sailing vessels in use today, including effectively all dinghies and yachts. The sheet on a fore-and-aft sail controls the angle of the sail to the