Taking account of solutions from ECMWF and other models - Grand Ensembles
An ensemble of NWP model runs using different models but starting from the same data times is known as a grand ensemble. Combining the current ensembles from different models into a larger ensemble (as in Fig6.1.1.1-1) can show possible consistency in forecasts and identify any different evolution.
It is inappropriate to rely on the results of any individual ensemble member or ensemble run itself. But if there is some indication of extreme or hazardous weather the threat should be passed on to users, but with a very low probability. Nevertheless, there can be some agreement between the spread and jumpiness.
Fig6.1.1.1-1: Schematic illustration of the relation between the latest Ensemble forecasts (green lines), the three latest Ensemble Control Forecast (ex-HRES) solutions (red lines), and results from other forecast models (blue lines). Here the two latest Ensemble Control Forecast (ex-HRES) solutions are broadly in agreement with the latest ensemble solution (green) but some other forecast models (blue) show some more extreme troughs or higher maxima.
Overview
Community Forums
Content Tools