河北北部强降雪统计特征及预报  

Statistical Characteristics and Forecasting Methods of Heavy Snowfall in Northern Hebei Province

作　　者：杨杰 范俊红 段宇辉 王宏 YANG Jie;FAN Junhong;DUAN Yuhui;WANG Hong(Chengde Meteorological Bureau,Chengde 067000,China;Hebei Meteorological Service Center,Shijiazhuang 050021,China;Hebei Meteorological Observatory,Shijiazhuang 050021,China)

机构地区：[1]承德市气象局,河北承德067000 [2]河北省气象服务中心,河北石家庄050021 [3]河北省气象台,河北石家庄050021

出　　处：《沙漠与绿洲气象》2022年第1期48-55,共8页Desert and Oasis Meteorology

基　　金：河北省科技厅科技支撑计划项目(14275402D);河北省预报员专项(17ky29)。

摘　　要：利用1986—2016年常规观测资料和NCEP(1°×1°)再分析资料,对承德市强降雪的环流背景和物理参数进行分析,总结出承德市强降雪特征及预报方法。结果显示:强降雪集中发生在11、2和3月;最早发生在10月,最晚结束于次年3月。承德市南部的强降雪过程多于北部。过渡季节的强降雪过程常伴有降水相态转换,降水量级明显大于冬季。强降雪类型可以分为回流型、地面低压型和弱流场型3类;当出现前两种天气形势时,且水汽含量>8 mm,700 hPa比湿>2 g/kg,对流层低层水汽通量散度值<-0.2 g/(hPa·cm^(2)·s),承德很可能发生强降雪。Based on conventional observation data and NCEP (1°×1°)reanalysis data from 1986 to2016,the circulation and physical parameters of heavy snow in Chengde were analyzed,and the characteristics and forecasting methods were summarized.The results show that heavy snowfalll in Chengde mainly concentrates in November,February and March.The first heavy snowfall tends to occur in October and the latest in the next March.There are more heavy snowfalls in the south than that in the north of Chengde.The heavy snowfalls in the transition season are often accompanied by changes in precipitation phase,and the precipitation amount is significantly more than that in winter.The types of heavy snowfall can be divided into three categories,which are backflow type,surface low pressure type and weak flow field type.When the first two weather conditions are formed,the water vapor content is greater than 8 mm,the specific humidity at 700 hPa is greater than 2 g/kg,and the moisture flux divergence in the lower troposphere is less than-0.2 g/(hPa·cm^(2)·s),heavy snowfall is very likely to occur in Chengde.

关 键 词：强降雪 统计特征 天气学分型 预报模型 

分 类 号：P458.11[天文地球—大气科学及气象学]