Evaluation of Track Forecast Guidance from Global Models for Pre-genesis Disturbances

The skill of track forecast guidance from numerical models has steadily increased over the last couple of decades. At the same time, forecasts from global numerical models are also being used as guidance for predicting tropical cyclogenesis. In 2017, the National Hurricane Center will begin issuing track forecasts for pre-genesis disturbances (i.e., “Invest” systems). While some recent studies (e.g., Halperin et al. 2013) have begun to evaluate the performance of the global models at predicting genesis, little work has been done to date on evaluating the track forecast guidance from these models for pre-genesis disturbances.

The purpose of this paper will be to evaluate the track forecasting performance of various global models and their ensembles for pre-genesis disturbances. Track forecasts from the 2014 and 2015 Atlantic and eastern Pacific hurricane seasons will be evaluated for the National Weather Service's Global Forecast System (GFS), the European Center for Medium Range Weather Forecasting (ECMWF) global model, the Canadian Meteorological Center (CMC) global model, and the U.S. Navy Global Environmental Model (NAVGEM). In addition, track forecasts from each Center's ensemble forecast system will also be evaluated.