Abstract: A newly designed chart-fronal θse chart is presented as a tool for frontal analysis. This tool is applied to the analysis of the upper boundary of cold-wave fronts in China for two cases. It is found that the θse over the upper frontal boundary is far from uniform and the θse value of maximum changes rather considerably with time. By means of this the authors try to demonstrate that the frontal surface is not a simple material surface always consisting of same set of air particles, but rather a structure with its own mechanism of metabolism, subjecting continuously frontogenetic process. The significance of this findings for frontal analysis and numerical forecasting is also discussed.