The session will focus on the most recent developments in the field of ensemble techniques, ranging from its close connection to data-assimilation and nowcasting to how to access predictability in high resolution (1 km scale) forecast systems.

As such it may provide a platform for exchanging ideas on how to create and use an ensemble system for forecast lead times ranging from hours to a few days. In particular, the use of ensembles in predicting
hazardous weather from several hours ahead will be of interest.

The conveners invite papers on various issues associated with Ensemble
Forecasting for weather prediction, such as:
• representation of initial uncertainties in Global and Limited-Area Ensemble Prediction Systems, including interlinks between data-assimilation and probabilistic forecasting;
• representation of model or boundary uncertainties in Global and Limited-Area Ensemble Prediction Systems;
• results from experiments including major campaigns such as THORPEX Regional Campaigns, HyMeX, MAP D-PHASE, COPS, ETReC07;
• results from recent studies using TIGGE and TIGGE-LAM databases;
• use, verification and calibration methods of Ensemble Prediction Systems.