泰安市一次大雨-暴雨天气过程中小尺度成因分析

2009年夏季泰安市降水量较常年偏少11.1%,其中6月份偏少50.7%,7月18日第一场大范围强降水减弱了当地的高温闷热天气,同时初步缓解了渐露的旱情,由于雨势强劲,亦给当地造成了一定的经济损失。根据由天气图形势常规资料和物理量的综合分析表明,此次天气过程中低空急流的位置与以往夏季天气过程有所不同,出现在低压的北侧,加快了北方冷空气和水汽的输送;此外,低空急流出现和消失都早于风场辐合区,是低压发生发展的动力条件。由热源和水汽汇分析表明,此次强降水积雨云对流活跃,以对流性降水为主。

Meso and Micro-scale Analysis on A Rainstorm Weather Process on Jun.18

The precipitation in Taian City in summer of 2009 was fewer than ordinary year,reduced 11.1 percent,among which,50.7% reduced in June.The first large-scale heavy rainfall on July 18 reduced the local high-temperature hot weather,also grew out of an initial easing of the drought.As the strong rain also caused some of the local economic losses.General information on the weather map and the physical situation,a comprehensive analysis showed that in this weather,the location of low-level jet during the past summer,the weather process is different,it appears in the low pressure in the north,accelerated the northern cold air and water vapor transport,In addition,the appearance and disappearance of both low-level jet winds early in the convergence zone,is the development of low power conditions.From the heat source and moisture sink analysis showed that this heavy precipitation cumulonimbus convective activity to convective precipitation.