两次副热带高压外围沿海暴雨过程对比分析
Comparison Analysis of the Two Coastal Rainstorm Courses of Subtropical High Peripheral Precipitation
中文摘要：
2010年8月4—5日和8月21—22日两次天气过程都是在副热带高压外围产生的沿海大暴雨天气。利用常规观测资料、自动站降水资料、NCEP再分析等资料，从大尺度环流场、物理量场、数值预报产品等方面对这两次过程进行综合诊断分析，以为河北海岸带暴雨提供一定的依据。结果表明，这两次暴雨过程均具有河北海岸带夏季暴雨的特征，是典型的副热带高压边缘大暴雨天气。水汽通量辐合区与暴雨的落区有较好的对应关系，边界层附近水汽的输送对降水起增大作用，两次过程的不同点在于影响系统和对流稳定度。当T639模式降水产品预报秦皇岛有大到暴雨，且秦皇岛位于副热带高压边缘，此时应重点分析水汽通量辐合区、高能舌和上升速度大值中心叠加区域；如果该区域存在中尺度系统触发机制，则该区域可能是沿海暴雨到大暴雨的落区。
中文关键词：
副热带高压，暴雨，物理量场，对比分析
KeyWords：
subtropical high, rainstorm, physical feature, comparison analysis
Abstract：
Two coastal heavy rains on August 4-5 and 21-22, 2010 were caused by subtropical high. Based on the conventional observation data, precipitation data from automatic stations and NCEP reanalysis data from NCEP/NCAR center, it is diagnosed mainly from circulation situation, influence system, physic and numerical forecast products, providing a basis for coastal zone in Hebei heavy rains. The results indicate: both of the two processes, which happened against a favorable circulation background had the characteristics of the coastal zone in Hebei summer rainstorm, are typical of the subtropical high edge heavy storm. The rainstorm area which corresponded well with the convergence zone of vapor flux water vapor near the boundary layer has a growth effect on the precipitation. Differences appeared from the trigger mechanism and the stability of convection when it has big-heavy rains in Qinhuangdao according to T639 forecast production. If there is a trigger mechanism of mesoscale system in such area, it will probably be the falling area of coastal heavy rains.