Verification of Met Office Global Icing Potential Forecasts using Satellite Observations

To ensure worldwide aviation safety, the World Area Forecast System (WAFS) provides global gridded forecasts of major meteorological hazards to aviation: in-flight icing, turbulence and cumulonimbus clouds. As a World Area Forecast Centre (WAFC), WAFC London produces forecasts of mean and maximum icing potential on a 1.25 degree global grid.  These forecasts are combined with icing potential forecasts issued by WAFC Washington to produce harmonised forecasts available to the global aviation community.

Recent instrument developments to the geostationary EUMETSAT Meteosat Second Generation (MSG) and Japan Meteorological Agency Himawari-8 satellites provide additional information about cloud properties to help identify areas conducive to icing.  The Met Office uses this information to produce a satellite icing potential product to aid forecasters in predicting in-flight icing. Icing potential satellite observations are updated every 15 minutes on a 0.25 degree grid with current coverage over Europe, North Atlantic, Africa and Asia.   

In order to assess the skill and reliability of icing potential forecasts, work has been carried out to investigate how to use the satellite icing potential product to produce objective verification.  Various challenges were assessed and assumptions were made in obtaining the most appropriate methodology, due to the differences in the forecast and observational products. This verification will aid the improvement of icing algorithms and evaluate the value of these forecasts to their users.