Contour analysis of meteorological factors is the indispensable tool for meteorological service, and the color map based on automatic filling of contours was widely used in the spatial analysis of meteorological element field. The most critical step of isolines color filling is determining the attributes of the regions and sorting. Generally, it was needed to judge the inclusion relation between grid points and regions, regions and regions. As its complexity, this method would occupy a large amount of RAM, and it would affect the computational efficiency. This paper presents a method to replace the traditional judgment of inclusion relation as positional relation judgment which can effectively simplify the contours color-filling with reduced difficulties and complexities. For the discrete data, dense isolines between two neighboring points have no practical significance, and they would affect the visual effect of spatial distribution. Based on the orderly marking of equivalent points on the same grid side, a method to automatically hiding partial isolines is proposed in this paper. It would effectively improve the visual effect of spatial distribution of dispersed field.