Forecasting Fog with a Very High Resolution Model

Fog formation is particularly challenging for numerical weather prediction models to accurately capture, due to its dependence on unresolved processes, both in the atmosphere and land-surface. The Met Office has recently started testing a 333m horizontal grid-length model covering the Greater London area, and we investigate the ability of this model to simulate foggy events. Better representation of surface characteristics, e.g. the orography and surface type, generally lead to improvements in the fog coverage. However, larger scale errors in temperature and moisture fields inherited from the driving model can still lead to large errors in fog prediction.