This paper explores the evolution of the helicity and Q vector before and after landfall of the typhoon and the formation cause of rainstorm during the typhoon in Zhejiang and Fujing provinces.

• 应用螺旋度和Q矢量的理论与方法，着重研究了台风登陆前后螺旋度和Q矢量散度场的演变特征，探讨了台风在浙闽地区造成的强降雨的基本成因。