一次区域性暴雪天气过程的诊断分析

利用Micaps常规天气资料和NCEP 1°×1° 6h再分析资料．采用天气学诊断方法．对2006年2月27日十堰市出现的一次区域性暴雪天气过程的环流特征和物理量场特征进行了分析。结果表明，此次区域性暴雪天气过程是在比较有利的天气背景条件下发生的，高空东移小槽、中低层切变线和地面冷锋是其主要的影响系统；中低层较强的暖湿气流（暖平流）沿低层冷空气垫爬升是产生强降雪的动力条件；强烈的水汽辐合为暴雪的产生提供了充足的水汽，暴雪区位于近似西南-东北向水汽通量轴线的左侧。

Diagnostic Analysis of a Regional Snowstorm Process

Based on conventional Micaps weather data and 1°×1° 6 h re-analysis data from NCEP, the circulation characteristics and physical characteristics of a regional snowstorm weather which occurred in Shiyan,Hubei province on 27 February 2006 are analyzed by using weather diagnosis methods. The results showed that the regional snowstorm process occurred in the relatively favorable weather conditions. The small trough moving eastward at the upper level, the shear line in the mid-and low-level and the cold front on the ground are the main impacts on the weather-scale systems. The stronger warm and wet airflow ascending in the mid-and low-level along the cold air cushion at the low level is the dynamic condition of the regional severe snowfall. The strong water vapor convergence provides the favorable moisture for the regional snowstorm process. The snowstorm area is located at the left of the water vapor flux axis being similarly southwest-northeastward.