[ Objective] The research aimed to analyze a local snowstorm weather process which happened in Beijing, Tianjin and Hebei during I - 4 January, 2010. [ Method] Based on routine meteorological observation data and NCEP...[ Objective] The research aimed to analyze a local snowstorm weather process which happened in Beijing, Tianjin and Hebei during I - 4 January, 2010. [ Method] Based on routine meteorological observation data and NCEP/NCAR 2.5° ×2.5° grid data (four times every day), a lo- cal snowstorm weather process which happened in Beijing, Tianjin and Hebei during 1 -4 January, 2010 was carried out diagnostic analysis by using composite analysis method. [Result] Circumfluence on the ground and strong cold advection in the rear of upper trough were the main weath- er system of the snowfall. The deep thick wet layer and strong water vapor convergence provided sufficient water vapor for snowfall. The divergence field of low-level convergence and high^level divergence, dynamic coupling effect of vorticity provided favorable dynamic condition upwardly for the occurrence of strong snowfall. The steep dense area of Oso, low temperature at the ground layer and inversion temperature at the high layer provided certain energy condition for the development of snowfall weather. [ Conclusion] The research provided theoretical basis for snowfall forecast in future.展开更多
文摘[ Objective] The research aimed to analyze a local snowstorm weather process which happened in Beijing, Tianjin and Hebei during I - 4 January, 2010. [ Method] Based on routine meteorological observation data and NCEP/NCAR 2.5° ×2.5° grid data (four times every day), a lo- cal snowstorm weather process which happened in Beijing, Tianjin and Hebei during 1 -4 January, 2010 was carried out diagnostic analysis by using composite analysis method. [Result] Circumfluence on the ground and strong cold advection in the rear of upper trough were the main weath- er system of the snowfall. The deep thick wet layer and strong water vapor convergence provided sufficient water vapor for snowfall. The divergence field of low-level convergence and high^level divergence, dynamic coupling effect of vorticity provided favorable dynamic condition upwardly for the occurrence of strong snowfall. The steep dense area of Oso, low temperature at the ground layer and inversion temperature at the high layer provided certain energy condition for the development of snowfall weather. [ Conclusion] The research provided theoretical basis for snowfall forecast in future.