Mesoscale simulation of tropical cyclone Amphan over Bay of Bengal: inter comparison with NCEP and NCUM global models.

In this study, a super cyclonic storm (Amphan) over Bay of Bengal was analyzed with the National Center for Medium-Range Weather Forecasting, Unified Model (NCUM) and National Center for Environmental Prediction (NCEP) global model data. Further, the weather research and forecasting (WRF) model has been utilized to simulate this super cyclonic storm with NCUM and NCEP data as initial and boundary conditions. The model is integrated, for every 12 h interval from 16 May 0000 UTC to 18 May 1200 UTC with horizontal resolution of 9 km and vertically at 34 levels. The results reveal that the track of the cyclone, central pressure of the cyclone, intensity of the cyclone, and landfall time of the cyclone are simulated by the model reasonably well in both the cases that are with NCUM-GFS and NCEP-GFS. However, the WRF simulations with NCEP data are closer to IMD's estimated track and intensity, when compared with the simulations with NCUM data. The relatively higher errors in simulations with NCUM could be due to the differences in the initial cyclone vortex against the observation in some initial conditions. [ABSTRACT FROM AUTHOR]