A "Weather Working Day" is a term used in the shipping industry to describe a day on which weather conditions are suitable for loading or unloading cargo from a vessel. This term takes into account various weather-related factors, such as wind speed, wave height, and visibility, and is used to determine whether it is safe and practical to carry out cargo operations. Weather Working Days are important for ensuring the safety of personnel and equipment involved in cargo operations, as well as for minimizing delays and disruptions to shipping schedules. In some cases, contractual agreements between shippers and carriers may specify certain requirements or allowances for Weather Working Days.