 According to the JMA track, the system turned southwest into the Gulf of Tonkin, intensifying slightly before shifting southeastward and dissipating over Hainan on September 4.Typhoon Wanda was fairly well-forecasted, compared to other storms during the year.The average forecast error for 24 hours was about 260 km (160 mi), whereas for 48 hours, it was 415 km (255 mi); both values were less than the seasonal average.