Abstract:The verification and analysis on tropical cyclone (TC) ensemble forecast of European Centre for Medium-Range Weather Forecasts (ECMWF) over western North Pacific in 2009-2015 are given from four aspects. The results show that the capability of ensemble forecast on TC tracks has been improving annually, but the intensity forecasting is always weak. The stronger the TCs are, the more accurate the ensemble forecasts of TC moving speed and moving direction are, though the forecasted speed is slow and the forecasted direction turning leftwards exists, whereas the forecasted intensity is weaker. On the other hand, the steering flow of TCs is classified into three grades. When the steering flow is weak, the TC moves slowly, and the direction forecasting is uncertain; when the steering flow is strong, the TC moving direction forecasting is reliable, but the speed forecasting is not good enough. As to the TCs over South China Sea classified according to three different types of tracks, the speed and direction ensemble forecasting errors would be small in westerly and northwesterly tracks, but would be large in westerly to northerly tracks. For the TC with westerly to northerly tracks, the direction forecasting has large spread before turning northerly, while the moving direction would be stable after turning northerly.