An Overview of Recent COAMPS-TC Performance and 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 2016 and 2017 including: i) increased horizontal resolution, ii) improved vortex initialization, iii) new tropical cyclone boundary layer and surface drag parameterizations, and iv) inclusion of more complete air-sea coupling. The COAMPS-TC has been operationally worldwide at a horizontal resolution of 4 km in 2017. The development of our system 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 operational COAMPS-TC forecasts for 2015-2017 in the Atlantic, E. Pacific and W. Pacific basins reveals much improved COAMPS-TC track, structure, and intensity predictions, and on par or in some aspects superior to any of the other operational dynamical forecast models.

Results for a high-resolution (4 km) COAMPS-TC ensemble with 11 members 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 includes a 20 member high-resolution HWRF ensemble. The results show considerable promise for probabilistic intensity and track prediction using a multi-agency, multi-model tropical cyclone ensemble approach.