福建春季冰雹天气物理量诊断分析

Diagnostic Analysis of Hail Events in Springtime in Fujian Province

利用1980～1999年高空探测资料的合成分析,总结出福建区域性降雹的环境场特征,造成福建冰雹的天气型主要为冷切适中型、低涡冷切适中型、低涡冷切偏西型、冷切偏南型、冷切偏西型.福建春季冰雹的主要机理是冷空气与强暖湿气流相遇而引发的.高空西风槽和南支槽及其前侧的副热带急流和低空强西南气流及准静止切变线是诱发福建省春季冰雹最主要的天气系统.同时还分析总结出冰雹过程的热力条件、动力条件、水汽条件等物理量特征.冰雹过程,福建处在高能区、强位势不稳定区和水汽通量高值区,低层辐合、高层辐散的上下层配置有利于福建省对流天气发展.

Base on the compound analysis of radiosonde data from 1980 to 1999, the ambient fields of hail events in springtime in Fujian Province were summarized. The main weather patterns which engender hails in Fujian are： moderate cold shear, moderate vortex and cold shear, westward deflection vortex and cold shear, southward deflection cold shear, and westward deflection cold shear. The main influencing weather systems are： upperlevel westerly trough, southern branch trough, subtropical jet, strong low-level southwest jet and quasi-stationary shear line. An analysis was made of the thermal and dynamic conditions and water vapor conditions during the hail events. It is found that Fujian Province was in the area of high-energy, strong potential instability, and high water vapor flux during the hail events. It was in favor of the convection development over Fujian Province that there was convergence at the low level and divergence at the upper-level.