Meteorological data from numerical weather prediction or observations for dispersion modelling

Synoptic observations of wind speed, direction, cloud cover, precipitation and temperature are inputs to regulatory dispersion modelling. Numerical Weather Prediction (NWP) data generated by national meteorological services are easily formatted for dispersion models. Changing from observations to NWP data raises concerns amongst regulators and model users – how might impact assessments differ if the source of meteorological data is changed. It is important to identify factors influencing the acceptability of NWP data. This paper compares numerical and surface synoptic meteorological data at locations across the UK. Further work is needed to harmonise the regulatory use of meteorological data.