Track Forecast Experiments of Typhoon Yagi 2013 with Atmospheric General Circulation Models

Factors causing diversity of operation forecast tracks for Typhoon Yagi 2013 are examined in forecast experiments using ECMWF OpenIFS. The models at three different horizontal resolutions were run from the initial conditions at 12 UTC 9 June prepared from the ECMWF analysis. The finest resolution model predicts northeastward migration and intensity closest to the operational ECMWF forecast, while the coarser models show erroneous westward bias and underdevelopment. Our experimental results suggest that the difference in the track may be attributable to the representation of the trough along the Baiu frontal zone through the change in the steering flow.