Current status of tropical cyclone track prediction techniques and forecast errors
Authors: GUPTA AKHILESH 
Published: November 2021

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Thanks to advanced data assimilation techniques, continuous model development, higher resolutions, and vortex specification, there has been considerable progress in the reduction of global tropical cyclone forecast errors during past few decades. It has been observed that world-wide rate of reduction of forecast errors was of the order of 1%-2% per year for all time horizons, with most rapid improvement at longer durations (beyond 48 hours). While other basins like Atlantic and Pacific oceans reported greater rate of decline of these errors due to various factors, the trend has been quite modest for Indian region. The only factor responsible for reduction of errors in the region was the greater use of synthetic vortex by operational NWP centres like India Meteorological Department (IMD) and National Centre for Medium Range Weather Forecasting (NCMRWF) in their Regional & Global model analyses. The current emphasis of international tropical cyclone research is to achieve greater accuracy of TC track prediction, especially in the short range, by maximizing the use of non-conventional data, meso-scale analysis, use of synthetic data for vortex specification, and the performance of physical parameterization at higher model resolution. The current research and operational emphasis of the ongoing Hurricane WRF project for land falling cyclones, is expected to benefit the Indian region in the years to come. Nevertheless, the Indian region needs to assign higher priority to the greater availability of conventional & non-conventional data and use of advanced data assimilation technique for model analysis besides its concerted efforts on model developments.