一次东风波中尺度暴雨的Q矢量与MM5预测能力对比

A Comparison of the Forecasting Abilities of Q Vector Divergence and MM5 Model for a Heavy Rain Caused by Eastly Wave

利用NCEP 1°×1°再分析资料对2001年8月3～4日的浙南闽北的东风波暴雨过程进行了分析。根据Q矢量散度分析讨论了这次过程中的暴雨演变以及东风波诱生中尺度低涡发生发展的原因。同时,利用中尺度有限区域模式MM5V2对该东风波诱生中尺度低涡进行模拟。结果表明:Q矢量散度大值中心强度和位置的演变较好反映了暴雨落区和中尺度低涡的诱生,其预示能力较MM5V2预报的准确率高,将中尺度模式和Q矢量计算结合起来可以提高风暴路径和雨区的预报准确率。

Using NCEP 1°× 1°reanalyzed data, a heavy rain process occurred in south seacoast of Zhejiang province caused by the eastly wave on August 3～4 in 2001 was analyzed, including its evolution and the cause of cyclonic vortex emerged by the eastly wave with Q vector divergence. Meanwhile, the process was simulated by MM5V2 model. Results show that the developing of center intensity and position of Q vector divergence maximum reflected the heavy rain and the emerging of cyclonic vortex, and the forecasting is more accurate than that of MM5 model, so combining Q vector divergence and MM5 model can offer the more correct weather forecast in similar to this weather process.