Subseasonal Forecasts of TC Activity in the Western North Pacific in Navy's Earth System Prediction Capability

Abstract We evaluate the ability of Navy's Earth System Prediction Capability (Navy ESPC) to forecast tropical cyclone (TC) activity in the Western North Pacific basin in the subseasonal timeframe. Navy ESPC forecasts of TCs were added to a logistic regression model that also incorporated the Madden‐Julian Oscillation (MJO) and El Niño Southern Oscillation to forecast basin‐wide TC activity. The skill of the statistical‐dynamical model at 14‐day lead times doubled when forecasted accumulated cyclone energy from Navy ESPC was incorporated into the model. This suggests that Navy ESPC TC tracks contain information that is independent from the MJO. An analysis of forecasted TC positions also suggests that the model has skill in forecasting TC track out to 21 days. These results suggest that combining TC tracks and large‐scale environmental information in a statistical‐dynamical model offers a promising path forward for predictions of basin‐scale or even sub‐basin‐scale subseasonal TC activity.