基于常规观测资料、NCEP1°×1°再分析资料和三门峡多普勒天气雷达资料，对2012年7月4日三门峡暴雨的环境条件、散度涡度场和中小尺度特征等进行了分析。结果表明：大暴雨过程中低层辐合高层辐散，促进气旋式涡度增加，上升运动增强；反之亦然。中层波动使得中低层辐合和中高层辐散更加深厚，进一步增强上升运动。西南暖湿气流北上受弱冷空气阻挡在三门峡地区堆积，为暴雨提供水汽和能量。南下的弱冷空气与辐合线和低层切变线组成强有力的触发抬升机制。暴雨期间多普勒天气雷达反射率因子、径向速度和风廓线产品，跟踪暴雨前后垂直方向风的变化和辐合系统，在强降水的临近预报中有较高的参考价值。%Based on conventional observations,NCEP1°×1° reanalysis data and Sanmenxia Doppler weather radar data,on July 4th,2012 Sanmenxia rainstorm environmental conditions,divergence and vorticity,small-scale features were analyzed. The results showed that during heavy rain the low-level convergence,upper-level divergence, promote the cyclonic vorticity increase,enhanced upward motion,and vice versa. Middle fluctuation makes the low-level convergence and upper-level divergence is more profound in senior,further enhances upward motion. Southwest warm air northward by blocking cold air accumulation in Sanmenxia area,provides moisture and energy for the storm. Weak cold air southward and convergence line and lower shear line composed of a strong lifting mechanism is triggered. Doppler weather radar reflectivity during rainstorms factor graph,figure wind profiler radial velocity product,and track after heavy rains in the vertical direction of the wind changes and convergence system,provide a important reference in heavy precipitation in nowcasting.
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