Ryota SAKAI
Numerical Prediction Division, Japan Meteorological Agency

Hiroshi MINO, Masashi NAGATA
National Typhoon Center, Japan Meteorological Agency

    The Japan Meteorological Agency (JMA) started operations of a new suite of numerical analysis and prediction models on a new computer system (Computer System for Meteorological Services, COSMETS) on 1 March 2001, including the Typhoon Model (TYM) and the Global Spectral Model (GSM) which make tropical cyclone predictions in the area of responsibility in the western North Pacific as an operation of the tropical cyclone (TC) Regional Specialized Meteorological Center (RSMC) Tokyo - Typhoon Center. Both horizontal and vertical resolutions were enhanced in TYM while only the vertical resolution was increased in GSM. These upgrades were expected to produce a higher performance of the models in tropical cyclone track and intensity predictions. However, verifications show that the track prediction performance of both models worsened, while the intensity prediction performance of TYM improved but that of GSM deteriorated. This paper summarizes major features of the verifications of tropical cyclone track and intensity predictions by TYM and GSM for the western North Pacific in the 2001 season.