EC细网格数值预报产品在一次降雪预报中的释用

EC fine grid numerical prediction product release in a snow forecast

应用常规气象资料和EC细网格数值预报产品,对2015年10月发生在兰州中川机场的一次降雪天气过程进行分析和预报释用,结果表明:空中较充沛的水汽含量、高原槽提供的较强的上升运动、空中及地面较强的降温导致了此次降雪天气过程的出现;EC细网格数值预报产品对此次降雪天气过程所需的环境条件反映的较好,通过对其预报的高空风温、2m温度、高空比湿、高空水汽通量散度与高空相对湿度这几个物理量的分析,可大致判断出降雪的主要时段及降雪的强度;EC细网格预报的逐3h降水量对此次降雪天气过程的降水时段具有较好的指示性,在对其他EC细网格数值预报产品分析的基础上再结合逐3h降水量的分析,可较为精细的预报出此次降雪天气。

In this article,using the conventional meteorological data and EC fine grid numerical prediction products,we analyzed a snowfall process that occurred in October 2015 in Lanzhou Zhongchuan airport. The results shows that,the higher humidity in the air,the strong ascending motion provided by the plateau trough and the relatively strong temperature decline both in high-level and surface-level lead to the occurrence of this snowfall process. And the EC fine grid numerical prediction products well reflected the environment condition for this snowfall process. By analyzing the physical quantities forecasted by EC,( include high-level air temperature and wind,temperature of 2 m,high-level specific humidity,high-level flux divergence of vapor,high-level relative humidity),we can make a general estimation of the main period of this snowfall process and intensity of the snow fall process. The precipitation production( per 3 hours) of EC fine grid,shows a well indication for the precipitation period of this snowfall process. Based on the analysis of other EC fine grid numerical forecast products,combining the analysis of The precipitation production( per 3 hours) of EC fine grid,we can forecast this snowfall process more accurately.