配料法在宁夏暴雨预报中的应用

选取2000—2015年发生在宁夏23次由深厚湿对流引起的区域性暴雨天气过程为研究对象,研究确定暴雨预报的配料方案,采用2016年6—8月宁夏25个常规站和947个自动站逐小时降水量、ECMWF 72 h内模式资料,从统计分析和个例剖析两方面探讨配料法暴雨预报效果,结果表明:(1)通过对比2016年6—8月ECMWF暴雨预报与配料法暴雨预报发现,不同预报时段,配料法暴雨预报均优于ECMWF暴雨预报;(2)配料法能准确预报所选两次暴雨个例降水的中心强度、落区及变化趋势,但强度和落区较实况偏强、偏大;(3)配料法对六盘山区暴雨过程弱降水预报效果较差,对贺兰山沿山暴雨过程存在降水空报。

Applications of Ingredients-based Forecasting Methodology to Rainstorm in Ningxia

Using the high-resolution numerical forecast physical quantity products of ECMWF and hourly precipitation observation data from 972 automatic weather stations in Ningxia, the ingredients-based methodology has been adopted to forecast rainstorm that made by deep convective system.Vertical velocity, atmospheric static instability and the low-level moisture were selected to be basic ingredients and the ingredients indicator was introduced. The relationship between the ingredients indicator and the precipitation has been obtained by linear regression analysis. The method has been used to forecast rainstorm that made by deep convective system in Ningxia. The ingredients-based methodology forecast effect to rainstorm was explored from two aspects of comparative analysis and case analysis, the results showed that: (1) Comparing the rainstorm forecast effect with ECMWF and ingredients-based methodology during June to August in 2016, the ingredients-based methodology skill score is superior to ECMWF in all forecast periods. (2) The ingredients-based methodology can forecast the precipitation intensity, precipitation trend and rainfall area of the two rainstorms. But the precipitation intensity is stronger and the rainfall area is wider. (3) The ingredients-based methodology forecast effect on light precipitation is inaccurate during the rainstorm process occurred at the Liupanshan Mountain. In addition, the precipitation area is vacancy in some area during the rainstorm process occurred at the Helanshan Mountain.