Next generation warning production system at MeteoSwiss

In the framework of the renewal of the warning system at MeteoSwiss, we use the possibility to redesign the software as well as the scientific approach of generating warnings. The production chain is designed such that the data is guided and refined along the pathway. Here, we present the operational production process currently in development for the next generation warning system. The first step is the combination of all available data into one data stream (seamless weather). The second stage prepares warning proposals for the forecasters. The only human interaction with the system (third step) is the one of the forecaster in case of extreme weather. However, the automatically generated warning proposals aim to minimize the time needed by the forecaster to issue a warning. In a last step at the end of the chain, the warning products are customized and distributed to our customers. Furthermore, the warnings will also be verified automatically to monitor the quality of the system. Along the chain, we run into a number of challenges, which ask for clever solutions: How do we group grid cells with similar extreme weather information into meaningful warning polygons? How do we facilitate the interaction of the system with the forecaster? Which aspects of the warning do we verify? How do we judge the quality of the warning? Finally yet importantly, what does the warning that we issue actually mean? If we do not have a common understanding about what we are expecting to happen within a warning polygon a clear communication of uncertainties and measuring the quality of our warnings is impossible. Hence, the system involves new applications based on specific developments aiming at generating the greatest value for public warnings. Most of the warning chain is purely machine driven; nonetheless, the human interaction remains a key aspect of the new warning system.