兰州中低层风向与降水的关系

The Relation between precipitation and Wind Direction at Mid Lower Levels in LanZhou

对兰州单站探空资料７００ｈＰａ和５００ｈＰａ风向进行统计分析表明，兰州７００ｈＰａ风向既受复杂地形影响，又受天气系统影响。７００ｈＰａ的东北风和东南风与降水有较好的相关关系。７００ｈＰａ、５００ｈＰａ风向有机组合，其降水相关概率提高到７１％—８２％。

According to Statistical analysis of wind direction at 700 hPa and 500 hPa levelsin radiosonde data in LanZhou,it is indicated that wind direction at 700 hPa is influenced bycomplex topography and synoptic systems, Both northeast wind and southeast wind at 700hPa and precipitation have a good Correlation. As wind directions between 700 hPa level and500 hPa level are reasonably associated , its correlation probability of precipitation grows by afactor of 71-82 percent.