Airport Vicinity Icing and Snow Advisor: 11 November 2003 Case Study

Air traffic at airports can be considerably disrupted during winter weather such as a snowstorm and freezing precipitation. De-icing operations must commence, the total amount of traffic the airport can handle is often reduced, and delays and flight cancellations are common. In-flight icing is also a problem for aircraft on approach or taking off. MSC is developing a Nowcasting system to help provide decision makers (airport authorities, airline dispatch, ground de-icing crews, pilots, etc) with real-time, accurate, and up-to-date weather information to help alleviate the problems and to increase safety. The system is currently called the Airport Vicinity Icing and Snow Advisor (AVISA). This system uses numerical model data, pilot reports, ground sensor data (precipitation, ceiling, visibility, winds, etc) as well as remote sensing (satellite, radar, radiometer) information to provide the necessary Nowcasts out to approximately 6 hours. The limitations and strengths of some of the component inputs (e.g. model data, radar, radiometric, precipitation rate) will be discussed using experiences from the Alliance Icing Research Study II (AIRS2) which was conducted in the Ottawa-Mirabel area from 3 November 2003 to 12 February 2004. Emphasis will be placed on “Nowcasts” produced for the 11 November 2003 case study. Verification data will include observations taken from the NRC Convair-580 research aircraft which was flying over the Mirabel site on that day.