Human beings are subject to comprehensive influence of various meteorological elements.Quantitative description of man′s perception of weather makes it necessary to study comfort index,whereby to better serve the public.A study is done on comfort accordind to the weather conditions in Zhongshan,Guangdong.As a result of the comparative study of various comfort indexes,effective temperature (ET) is taken as the criterion for the judgement of comfort.In order to accurately depict man′s overall perception of weather,daily mean effective temperature (MEP) is calculated according to daily average states of various meteorological elements,which is then grouped into one of the nine categories.Analysis of daily mean effective temperature over the past year indicates that such a classification is satisfactory.Apart from MEP,corresponding ETs are also calculated separately for the periods of time when the highest and lowest temperatures are observed.Our program reacts satisfactorily when abnormalities occur in temperature,humidity,and wind force,thus giving the public necessary detailed description.The program has proved satisfactory in application.