Recent developments in the INCA analysis and nowcasting system

The high-resolution INCA system (Integrated Nowcasting through Comprehensive Analysis) provides gridded analyses and short-term forecasts of meteorological fields at a horizontal resolution of 1 km and at 5 to 60 min temporal resolution. After the nowcasting part, INCA fields are blended into AROME or a statistically optimized combination of NWP models, thus providing a seamless chain of forecasting fields at various scales. As an operational product of the national Austrian weather service (ZAMG), INCA is employed for a number of applications, such as for hydrological runoff modelling, severe weather warnings, in road safety, agriculture and in the renewable energy sector. The product development is embedded into the research activities of the last year period which, amongst others, included the development of new blending methods into the state of the art NWP models, a new approach for precipitation analysis and nowcasting as well as the evaluation of wind, temperature and humidity analyses at 100 m horizontal resolution. For precipitation, a new radar-raingauge merging algorithm has been developed, which is based on station density and radar minimum beam height. Precipitation nowcasting uses optical flow and nested subdomains for breaking down the displacement vectors to the target grid. In the sub-kilometer version, the improvements due to the topography-relevant features (i.e. altitude, slope) in Alpine areas are shown as well as the potential benefits of high resolution nowcasting in urban areas. The methods and related results will be presented along with a comprehensive verification.