Using opportunistic sensors in a new hydro-meteorological precipitation and flood forecasting system for small catchments

Small, fast responding catchments are prone to flooding induced by local convective precipitation events. In such cases, the availability of high-quality information as basis for target-oriented warnings and effective protective measures in potentially affected regions is essential. More precisely, they rely on high-quality precipitation data, reliable weather and flood forecasting and last but not least information and education of persons in charge for prevention of hazards.Within the project HoWa-PRO funded by the German Federal Ministry of Education and Research (BMBF) a new hydro-meteorological processing chain has been established to improve flood forecasting and warnings for small catchments. The system has been automated and a routine mode consisting of three main parts has been established:To produce high-quality Quantitative Precipitation Estimates (QPE) the Deutscher Wetterdienst (DWD) performs an operational gauge-adjustment of radar-based precipitation estimates. Within HoWa-PRO, the additional merging of precipitation data derived from numerous Commercial Microwave Links (CML) with high temporal resolution and low latency promises an improvement of capturing local extreme precipitation events leading to a multi-sensor QPE product optimized for convective weather. The QPE products together with forecasts from DWDs seamless prediction system SINFONY-INTENSE a combination of nowcasting and numerical weather prediction run in a Rapid Update Cycle (RUC) serve as input for a hydrologic ensemble prediction system designed for small catchments resulting in discharge time series including uncertainty information. To meet the requirements of communicating the uncertainty information of the ensemble forecasts to key clients in disaster and risk management, an information platform (howapro.de) with tailored visual information on flood early warnings for small catchments constitute the last part of the processing chain. In addition, a serious game has been designed for educational purposes. This contribution gives an overview of the whole processing chain and presents case studies and first verification results.