Abstract: It is very important to find and trace the weather system,such as severe convective clouds(SCC),which cause severe calamity.This paper describes the finding and tracing of SCC using computer image technique for GMS IR image. In this paper we put forward a segment smoothing filter algorithm and threshold algorithm to filter SCC in the IR image preprocessing. With respect to the filtered SCC, the T algorithm and IP algorithm of outline coding method in image processing are used to extract the boundary line and the first point in the line from SCC. The description of SCC includes four characteristic quantities, i.e. center of gravity, cloud size, moment invariant M and shape descriptor R. In this paper pattern recognition and pattern match technique are used to trace the SCC. Two pattern processes of recognition and matching, i.e. rough and fine comparative analysis,are provided . Rough comparative analysis includes the establishment of search area and size recognition, and fine comparative analysis is composed of shape descriptor R match, moment invariant M match and correlation-brightness analysis.