Verification on Forecasts of Tropical Cyclones over Western North Pacific in 2013
Operational positioning, track and intensity forecast errors of tropical cyclones (TCs) over western North Pacific in 2013 are evaluated on the basis of CMA/STI’s Best track dataset. Meanwhile, the systematic biases of both global and regional models in track and intensity forecasts are analyzed. The results show that the performance of TC positioning is a little better than that in previous years, with an average error by all methods is 21.7 km. The average track forecast errors by the subjective methods of each province or autonomous regions are 80.2 km (24 h), 143.3 km (48 h) and 221.7 km (72 h), which are reduced by 13.9%, 13.4% and 20.9% compared to those in 2012. And the 24 h track forecast error of National Meteorological Centre (NMC) of CMA is less than 90 km for the first time. Global and regional models have steady improvement in the performance of track forecast, however, the models also display specific systematic biases. The overall performance of statistical forecast method is still better than numerical prediction method in intensity forecast. In the numerical prediction methods, the performance of regional models is slightly better than global models. Some global and regional models also have systematic biases in intensity prediction. The subjective methods predict well the 24 h landfall location of Typhoon 1308 “Cimaron”, but are not so good for Typhoon 1306 “Rumbia”, Typhoon 1311 “Utor”, Typhoon 1312 “Trami” and Typhoon 1323 “Fitow”.