Towards Improved Intensity Prediction: An Overview of Recent COAMPS-TC Advancements

The Coupled Ocean/Atmosphere Mesoscale Prediction System for Tropical Cyclones (COAMPS-TC) has been developed for forecasting tropical cyclone track, structure, and intensity over the past several years and transitioned to Navy operations at the Fleet Numerical Meteorology and Oceanography Center in 2013. Here we provide an update on the latest advancements to the COAMPS-TC system in 2015 and 2016 including: i) improved vortex initialization and dynamical initialization methods, ii) new tropical cyclone boundary layer parameterization, and iii) inclusion of more complete air-sea coupling. The COAMPS-TC has been tested in real time in both coupled and uncoupled modes in the Pacific and Atlantic basins at a horizontal resolution of 5 km. The real-time testing has been motivated by several recent multi-agency programs and efforts that we will report on including: i) the Hurricane Forecast Improvement Project (HFIP), which is focused on the W. Atlantic and E. Pacific basins, ii) the recent NASA HS3 and ONR Tropical Cyclone Intensity field programs, and iii) real-time testing in parallel with the Navy operational version of COAMPS-TC in the W. Atlantic, E. Pacific and W. Pacific basin. An evaluation of a large sample of real-time forecasts for 2014-2015 in the Atlantic, E. Pacific and W. Pacific basins reveals much improved COAMPS-TC track and intensity predictions, and in many regards on par or in some aspects better than established operational dynamical forecast models. Progress on further improvements based on advancements to the data assimilation

Results for a high-resolution (3 km) COAMPS-TC ensemble that was run over the W. Atlantic and E. Pacific basins will be discussed. The COAMPS-TC ensemble was performed in collaboration with the HFIP program, which included high-resolution HWRF and GFDL ensembles. The results show considerable promise for probabilistic intensity and track prediction using a multi-agency, multi-model tropical cyclone ensemble approach.