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The Radar Coverage product shows the area covered by the OPERA pan-European radar composite. The product is computed once per hour to show the latest available observations, please see the instructions at the bottom of this page for guidance on loading this product into the EFAS web interface. The radar data are used to derive rainfall accumulation nowcasts which are input to the radar-based flash flood products, and therefore users are encouraged to use the radar coverage product to help interpret the radar-based flash flood impact products. For example, the urban flash flood products are not available in areas outside of the radar coverage. River flash flood impacts are forecasted in areas outside of the radar coverage using forecasts from the ECMWF NWP, which are expected to be less accurate in predicting extreme rainfall associated with convective conditions, furthermore the ECMWF NWP forecasts are only updated 4 times per day rather than every hour. We recommend to exercise caution when interpreting the river flash flood impact products in areas outside of the valid radar coverage.
Figure 1. Radar coverage product shown on the EFAS web interface for the 24th February 2025 at 12 UTC. The darker grey shades show where no radar data were available.
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