In order to find the seasonal regularities of upper respiratory tract infection for young children in Jinhua and its relations with climate,the apparent temperatures of young children were calculated based on human body heat balance.In the process of computation,three different environments(indoor,outdoor with and without shadows) were taken into account respectively.According to these results,the apparent temperatures,dekad maximum and minimum apparent temperatures,etc,were calculated.Then such techniques as linear regression analysis,natural empirical orthogonal function,and stepwise regression were integrated to establish the forecast models of upper respiratory tract infection.It was proved that the change tendency of fitting values from the model is almost identical with that of observational values in warm days and the peak values are also the same.Meanwhile,the change tendency of fitting values from the model was also basically similar with that of observational values in cold days.However,the peak values are not obvious,and the difference between fitting and observational values was comparatively great.