This three-hour lesson describes the impacts of weather on aviation operations and highlights the role of the National Weather Service (NWS) in supporting the Federal Aviation Administration's air traffic management organization. The lesson contains an Introduction (40 min), several cases (10-20 min each) focused on various weather phenomena, and a detailed case (35 min) allowing forecasters to follow the planning for and evolution of an event. The content emphasizes best practices for aviation forecasters, including identifying and communicating the threat, understanding partners' needs, and anticipating the impacts to airspace operations.