气象与环境学报Issue(3)：23-28,6.DOI:10.3969/j.issn.1673-503X.2015.03.004
河北省南部回流暴雪天气结构特征
Structural feature of return-flow snowstorm in southern Hebei province
摘要
Abstract
Using the conventional observational meteorological data from weather stations and snowfall data from intensive automatic weather stations as well as the NCEP reanalysis data with resolution of 1 °×1 °,two return-flow snowstorm processes on November 10-12,2009 and November 29-30,201 1 in the southern Hebei province were compared.The results show that spatial and temporal distributions of the two processes have mesoscale features. Low trough moves eastward at 500 hPa in Hetao area and it has shear line at 700 hPa;the Mongolian cold high pressure in the ground moves to east and arrives in the northeastern China,and inverted trough develops in Hetao area;surface pressure is higher in east and lower in west of the north China.All the mentioned-above are the typi-cal weather patterns of the two return-flow snowstorms.Upper-level and low-level jets play a very important role during the return-flow snowstorm.Cold air returns to the southern Hebei province with the northeast stream under 850 hPa and forms cold cushion.Moist air is transported into the southern Hebei province with southwest jet and convergence uplifts on cold cushion at 700 hPa.Upward movement is strengthened by divergence pumping action on the right rear side of 200 hPa upper-level jet.There is a vertical circulation in the North China plain.The north-east wind of boundary layer arrives in the east side of Taihang Mountain then lifts to mid-upper troposphere,and it becomes southwest wind and flows to northeastern China,where it becomes downward flow and finally forms a complete vertical circulation with low-level northeast wind.The intensive area ofθse stretches to 700 hPa from the ground,and frontal structure is obvious.Front advances from north to south.θse lines are upright from the ground to 850 hPa near the front.Atmospheric stratification is neutral convection stability.Return-flow snowfall happens in cold air mass after ground front.关键词
暴雪/冷空气回流/中尺度观测特征/高低空急流/锋面结构Key words
Snowstorm/Return-flow cold air/Mesoscale features/Upper-level and low-level jets/Frontal structure分类
天文与地球科学引用本文复制引用
王丛梅,李永占,刘晓灵..河北省南部回流暴雪天气结构特征[J].气象与环境学报,2015,(3):23-28,6.基金项目
公益性行业（气象）科研专项（GYHY201306008）和河北省气象局科研项目（11ky41）共同资助。 （）
