Southern hemisphere tropical cyclone intensity forecast methods used at the Joint Typhoon Warning Center, Part III: forecasts based on a multi-model consensus approach

Abstract

Consensus forecasts aids, those derived from forecasts from several models, and ensemble forecasts aids, those derived from several forecast created by a single model, have become commonplace. Consensus forecast aids are now an integral part of operational tropical cyclone forecasting at the Joint Typhoon Warning Center (JTWC). These consensus aids generally have lower average errors than individual forecast aids and benefit from the skill and independence of their members. This paper discusses the performance of one ensemble forecast aid and one consensus forecast aid run in real-time and made available to JTWC during the 2007 and 2008 southern hemisphere tropical cyclone seasons. The ensemble forecast aid is shown to be as skillful as the top performing ensemble member at each forecast time. The consensus forecast aid is shown to be the most skillful aid available to JTWC during the 2007 and 2008 seasons. Further experiments indicate that adding more forecast aids to the intensity consensus may marginally improve both skill and forecast availability of the consensus forecast aid