Abstract: There are extreme gusts and waves when the developing extratropical cyclones (DECS) enters the Zhejiang coastal waters, which can bring about shipwrecks and fatalities. In this study, the Weather Research and Forecasting (WRF) model system which is typically used in the regional meso-scale model prediction, was used to simulate a DECS process. Three experiments were conducted: experiment one (without assimilation data); experiment two (with assimilation of cloud drift wind data (CDWD), quality control was not conducted to the CDWD) and experiment three (with assimilation of CDWD, quality control was conducted to the CDWD). The comparison of the three experiments shows that including the assimilation of CDWD, they can have positive impact on DECS prediction. The results of experiment three are very similar to those of actual observation, therefore it can improve the prediction accuracy about the DECS which influence the Zhejiang coastal waters.

Key words: extratropical cyclone, cloud drift wind, numerical simulation, forecasting