Examination and Evaluation of WRF in Floods Season Precipitation Forecast of Jintan

Abstract

The WRF V2 model was examined and evaluated in the precipitation forecast of Jintan from May to September in 2008 using daily precipitation forecast of product information. through test and analysis to the forecast of single point precipitation. The results show that: (1) the precipitation forecast accuracy rate of each month of the single point (55%-75%) is about 10% lower than the regional (65% -85%). (2) the WRF V2 model has a moderate precipitation forecast accuracy rate (75%) for the rain or shine, moderate rain and less precipitation. However, when forecasting heavy rain and more precipitation, the model’s capability is weak. (3) the model has a higher probability of empty forecast (above 60%), and a lower probability of omission forecast. With the increase of the precipitation level, the empty rate reduced while the omission rate increased. (4) The stage precipitation forecast effect of 24h is better than 12h, namely, the forecast period is the longer, the smaller the error of the actual situations in precipitation, and the better effect of the simulation of the model.