鲁西北罕见的秋季连阴雨环流特征分析

利用常规天气图资料和NCEP提供的1°×1°FNL分析场资料等,分析了2007年9月26日至10月7日鲁西北秋季连阴雨期间大尺度环流及物理量特征.分析表明,连阴雨期间,亚欧上空大型环流相对稳定,乌拉尔山附近维持一稳定的阻塞高压,西太平洋副热带高压异常偏强,低纬地区热带气旋活动频繁,南亚高压和副热带急流位置明显偏北,亚洲中纬度多短波槽东移,700hPa鲁西北及其北侧多维持切变线,与副热带高压西北侧的西南暖湿气流在黄河中、下游一带持续相互作用,形成了长达12天的阴雨天气.

Analysis of a Rare Continuous Autumn Rain in Northwest Shandong

Based on the routine weather chart data and NCEP 1°×1°FNL grid data, it was analyzed the upper air circulation and physical features for a rare continuous autumn rain occurring in Northwest Shandong from September 26 to October 7, 2007.It is shown that the large scale circulation over Eurasia was relatively stable, a stable blocking anticyclone had been maintained nearby the Ural Mountains, the subtropical high pressure of the West Pacific was extraordinary strong, tropical cyclones were generated in the low latitude zone frequently, the positions of South Asian high and subtropical westerlies jet stream were obviously further north than normal, the short wave trough was continuously split up to move toward east in mid latitudes of Asia, and the southwest warm wet air currents of the northwest of the subtropical high continued to interact in the mid and lower reaches of the Yellow River, thus formed the 12 day long overcast and rainy weather.