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This paper discusses developments in the last five to six years in the provision of operational flood forecasting in England, Wales, and Scotland. Before the formation of the Environment Agency EA in England and Wales and the Scottish Environment Protection Agency SEPA, flood forecasting capabilities were fragmented. Just over a decade ago both organisations received governmental mandates for the provision of flood forecasting and warning nationally, and have as a result in recent years established systems providing national coverage: the National Flood Forecasting System, and Flood Early Warning System FEWS Scotland. These have facilitated a rapid expansion of catchments for which forecasts are provided, and the common framework used has enabled a more rapid introduction of scientific advances in forecasting techniques. This paper gives an overview of some of these recent developments, as well as providing an outlook to further developments to be undertaken in the near future. Copyright © 2009 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

ABSTRACT A lee wave forecast system has been run operationally at the UK Met Office since 2006. The forecasts are produced by a numerical model for flow over complex terrain (3DVOM) which is run for five separate hilly regions across the UK. These regions cover Dartmoor (southwest England), Snowdonia (north Wales), Cumbria and the Pennines (northern England), the Grampians (Scotland) and the Mourne and Sperrin mountains (Northern Ireland). Examples of verification of the model forecasts against aircraft and satellite observations are presented. Three years of forecast data for these regions have been used to generate a lee wave climatology for the UK. The model predicts large geographical differences, with lee waves occurring least frequently over Dartmoor and most frequently over Snowdonia and the Grampians. Large amplitude waves, with peak vertical velocities exceeding 3 m s−1 at 700 hPa or above, are more common in forecasts for the Grampian region than others. Lee waves occur more frequently in forecasts during winter months than in summer. The most favourable conditions are those in which there is little turning of the lower tropospheric winds and analysis suggests that the waves are typically trapped in the lower troposphere. The influence of the lee waves on the near-surface flow has also been investigated. Large accelerations and flow deflections can occur beneath the waves. It is suggested that the latter correspond to turbulent lee wave rotors. Preferred locations for this behaviour have been identified in the model forecasts for the Grampians and Pennines. [ABSTRACT FROM AUTHOR]