The regional trends in UK visibility and other meteorological parameters (relative humidity, temperature, wind characteristics) were quantified for the last 60 years using datasets collected by the UK Met Office. Clear trends are observed in long visibility change. This change in visibility can be related to the changing aerosol concentrations and compositions. Furthermore, we clearly demonstrate the role of hygroscopicity on aerosol particle growth impacts upon the extinction properties of aerosol and hence UK visibility. Long term changes in relative humidity result in long term changes in visibility.