使用NCEP/NCAR 1°×1°格点资料，对2010—2011年冬季浙江两次强降雪进行了对比，通过对环流形势、水汽、动力、热力特征的诊断分析表明，2010年12月15日降雪过程是一次高空横槽转竖，地面强冷空气南下的冷过程，而2011年1月18—21日降雪过程是冷背景下西南气流北抬的暖过程；在700hPa两者都存在着西南气流的加强；850hPa，前者是东风急流，后者是西南风急流。两次降雪都有充分的水汽和强烈的垂直上升运动，前者能量锋区是南压的，而后者是南北波动的；两次降雪都满足温度场的基本条件，并具有逆温结构，前者的逆温层深厚，后者的比较浅薄。

Using the NCEP/NCAR 1°×1° grid data, two of the heavy snowfall occurred in the winter of 2010—2011 in Zhejiang Province were studied. Based on the diagnostic analysis on the circulation over the high and low level, the moisture conditions, the dynamic field and the thermal characteristics and the comparison of the two heavy snowfall, the results indicate that the snowfall on December 15, 2010 was a cooling process with the erection transfer of high-altitude horizontal groove and strong surface cold air blowing southward, meanwhile the snowfall on January 18—21, 2011 was in the cool context with southern branch trough deepening and moving eastward and the warm-wet southwest wind blowing northward, the ground was within the control of cold high variability. At the middle level, for both cases, the augment of the southwester flow exists. Over the low-level, the former water vapor was transported by east jet, while the later water vapor was transported by the southwest air. The two processes require adequate supply of water vapor and vertical ascending motion. Energy front of the former is the southward, while the energy front of latter is a north-south fluctuation. Two processes both meet the basic conditions of temperature field and have the structure of a temperature inversion. However, the former has a strong inversion layer, while the latter is relatively shallow.