利用WRF模式制作东北地区冬季降水相态预报

利用WRFV3.1.1中尺度数值模式，对东北地区冬季降水相态进行预报尝试。在模式预报输出场中，通过对近地面大气层中冻结部分降水混合比在可凝结成降水的水汽混合比中的比例，来判断雨雪分界线及雨夹雪区或雨、雪过渡区。结果表明：该方法可较准确预报出降水过程中雨区、雪区和雨夹雪区的分布特征以及降水相态随时间的演变情况。降水相态数值预报产品的应用能够明显提高冬季气象预报服务水平。

Forecasting of winter precipitation phase state in Northeast China based on WRF mesoscale model

The forecasting of winter precipitation phase state in the Northeast Chinawas attempted with a  mesoscale numerical weather prediction model (WRFV3.1.1). According to the percentage of frozen fraction of precipitation mixing proportion in atmosphere near the ground in water vapor mixing proportion that may condense into precipitation, the rain snow boundary line, sleet area, the transition zone of rain snow were determined. The results indicate that this method could forecast  the distribution areas of rain, snow and sleet and the evolution of precipitation phase state during precipitation process with a relatively good accuracy. The application of these numerical forecast products  could significantly improve the accuracy of weather forecast .