Prediction of tropical cyclone intensity and track using COAMPS-TC

A new version of the Coupled Ocean/Atmosphere Mesoscale Prediction System for Tropical Cyclones (COAMPS-TC) has been developed specifically for forecasting tropical cyclone track, structure and intensity. The COAMPS-TC has been tested in real time in both coupled and uncoupled modes over the past several tropical cyclone seasons 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: i) the Hurricane Forecast Improvement Project (HFIP), which is focused on the W. Atlantic and E. Pacific basins, ii) the 2008 ONR THORPEX Pacific Asian Regional Campaign (T-PARC) and the ONR Tropical Cyclone Structure-08 (TCS08) and 2010 Interaction of Typhoon and Ocean Project (ITOP), which took place in the W. Pacific, and iii) pre-operational testing of COAMPS-TC in W. Pacific basin. An evaluation of a large sample of real time forecasts for 2010-2011 in the Atlantic basin reveals that the COAMPS-TC intensity predictions are more accurate than any other real time dynamical forecast models, particularly beyond the 36 h time. As an example, real-time forecasts for Hurricane Irene (2011) illustrate the capability of COAMPS-TC to capture both the intensity (see Figure) and the fine-scale features in close agreement with observations. Evaluation of real-time COAMPS-TC forecasts will be presented using the TCS08, ITOP, and HFIP datasets with a focus on challenges and successes related to tropical cyclone intensity prediction. Additionally, highlights from a ten member 5 km horizontal resolution COAMPS-TC ensemble that was run over the W. Atlantic and W. Pacific basins during 2011 will be presented. The results of this research highlight the promise of high-resolution deterministic and ensemble-based approaches for tropical cyclone prediction using COAMPS-TC.