【摘要】 本文通过对北方地区两次低空东南风急流的对比分析,指出:低空急流附近有无暴雨发生与其本身结构特征有关。它们在湿度、三维流场以及急流本身的稳定性等方面,有很大的差异。因此在讨论低空急流与暴雨的相互作用时,不能只注意到低空出现了强风,甚至有明显的水平和垂直切变。如果它不具备有利于暴雨发生的热力和动力条件,那它就可能是一次“空急流”。更多还原

【Abstract】 In this paper,two cases of low level,southeastly jets in North China are com-pared.It is found that whether there will occur heavy rain near the jet or notdepends on its structure.There are marked differences between them in moisturetransfer,three-dimensional flow and stability of the jets.In the forecasting ofrainstorm,it is insufficient only to pay attention to the strength of wind,even witha remarkable horizontal and vertical shear.Favorable thermal and dynamic condi-tions are necessary for rainstorm.更多还原