西南低涡暴雨的湿位涡诊断分析

文章分析了１９８１年７月１１－１５日的一次与西南低涡有关的四川特大暴雨过程中的湿位涡变化，发现湿位涡由负变正预示着暴雨的威弱和消失；同时利用湿位涡方程进行了诊断计算，结果表明：暴雨的发展趋势与位涡变率的变化趋势基本一致，位涡变率的正负转换对预报大暴雨的形成和减弱有一定的指示意义。

The Diagnostic Analysis of Wet Potential Vorticity of Storm Rainfall from the Southwest Vortex in China

Adiagnostic analysis of the wet potential vorticity of the storm rainfall relating tothe southwest vortex in Sichuan Province of China(11-15 July,1981) is made. Theresults show that the change of wet potential vorticity from positive values to negativevalues indicates the decline and elimination of storm rainfall.Furthermore,according tothe wet potential diagnostic equation,it is found that the variation tendency of stormrainfall basicallv coincides with the variation tendencv of wet potential vorticity, and themathematical symbols changes of wet potential vorticity indicate the formation or thedirnination of storrn rainfall.