The freezing rain and snow seriously affect traffic, electric power and so on all walks of life. Through the construction of a monitoring system, we add more observation elements such as snow depth, weighing precipitation， realscene observation and so on, and strengthen the automatic monitoring of snow condition and solid precipitation. Using OpenCV technology to control the quality of snow depth monitoring data, the wContour class library drawing method is used to draw the contour map in combination with the realscene photos to timely and accurately reflect the freezing rain and snow situation. By the analyzing system, integrating other meteorological observation data and using contour map, we provide intuitive and accurate weather information for meteorologists and decision departments, and further provide effective technical means for meteorological disaster prevention and mitigation, to improve the level of meteorological service.