Recent developments in countrywide flood forecasting using the G2G distributed hydrological model

New countrywide Flood Forecasting Systems based on the Grid-to-Grid (G2G) distributed rainfall-runoff and routing model have been implemented across Britain for use by the Flood Forecasting Centre and Scottish Flood Forecasting Service. This has achieved a step-change in operational capability with probabilistic forecasts of flooding several days ahead “everywhere” on a 1 km grid now possible. Ongoing work is assessing use of G2G for flood forecasting in Rapid Response Catchments and prototyping its potential use for surface water flooding. The national scale distributed hydrological modelling approach also provides a powerful framework for addressing other hydrological and environmental issues. An overview of these recent and ongoing developments of G2G for flood risk management related applications is provided.