The INCA-BE system: ten years of operational nowcasting and its applications at the national meteorological service of Belgium

Operational nowcasting systems are often key elements in meteorological services worldwide, e.g., in issuing severe weather warnings. Unfortunately, the documentation on these systems is not always available, which - on its turn - slows down the development and the international collaboration in this field. This technical publication is an endeavour to fill this gap between research and operations by describing the recent improvements in INCA-BE, the operational nowcasting system of the Royal Meteorological Institute of Belgium (RMIB). Several of the recently developed system extensions are discussed, including: the nowcast of lightning, the nowcast of hail, the generation of an uncertainty plume in the precipitation forecast, and the nowcast of 10m wind gusts. The INCA-BE output is exploited in numerous downstream applications, of which two are discussed in more detail: (1) a tool to detect hazardous precipitation accumulations by a real-time combination of the precipitation nowcast and return period information; (2) a unique system allowing human intervention in the generation and dissemination of smartphone notifications for severe weather. These recent developments contribute to the refinement of both the manual and automatic warnings for meteorological hazards in Belgium, not only at RMIB itself, but also in the regional hydrological and road management services.