暖锋锋生引发中尺度暴雨的环境条件及诊断分析

Environmental conditions and diagnostic analysis of the mesoscale rainstorm caused by the warm frontogenesis

2012年7月28-30日,黑龙江省受暖锋锋生影响,自西南向东北出现区域性暴雨天气过程。此次暴雨天气过程,降水持续时间长,影响范围广,显著特点是短时局地暴雨强度大,多站降水量超过100 mm,黑龙江省罕见。通过对暴雨产生的主要环境条件及中尺度分析,得出结论:暴雨主要是河套低压北上、暖锋影响产生的,暖锋锋生及锋前对流触发是短时降水增强的原因。低空西南急流为暴雨区带来了丰富的水汽和不稳定能量,高低空急流耦合加强了动力条件。弱干冷空气入侵增强暖锋降水,地面中尺度环流的建立及增强与降水强度增加对应。

A regional rainstorm happened from the southwest to the northeast of Heilongjiang province during July 28-30, 2012, which was influenced by warm frontogenesis .The precipitation of this weather process last long time and influenced a wide range.Its significant features is the heavy precipitation intensity, and Multi-station precipitation exceeded 100 mm which barely happened in Heilongjiang province. Analyzing the background environment of rainstorm, the results showed that the rainstorm was caused by the northward moving of Hetao low pressure and the warm front, the main reason for the frontogenesis and the convection before it. The southwest strengthening of short-time precipitation is the warm low-level jet brought abundant moisture and unstable energy to the heavy rain area, high and low level jet coupling enhances the dynamic conditions. Intrusion of the dry cold air enhanced the warm front precipitation, the establishment and enhancement of ground mesoscale circulations correspond to the increased precipitation intensity.