Use of OPERA Data for Real-Time Pan-European Flash-Flood Hazard Assessment and Nowcasting

Near-surface radar reflectivity observations meet the requirements of flash floods detection and forecasting, thanks to their capability to capture the short-term evolution of the rainfall field at high temporal and spatial resolution. Also, the improvements in national and transnational operational radar networks provide improved rainfall observations and rainfall nowcasting that can help identifying and anticipating the areas potentially affected by the hazards associated to heavy rains.

We present flash flood events occurred in Europe during 2015-2017 and identified by the real-time flash flood module of the European Rainfall-InduCed Hazard Assessment (ERICHA) system (and recently implemented in the European Flood Awareness System, EFAS). This flash-flood forecasting module is based on the rainfall inputs from the European radar reflectivity composites generated by the EUMETNET project OPERA (Operational Programme for the Exchange of weather RAdar) with resolutions of 2 km, 15 minutes.

Because the performance of the tool is critically affected by the quality of the radar quantitative precipitation estimates (QPE), the presentation will focus on the status of radar QPE using raingauge measurements throughout Europe. The impact of the QPE to the hazard identification and assessment will be illustrated through the selected events.