An analysis procedure based on derivation of an analytic formula containing two or more variables to approximate values of a physical quantity at specified data points. The resulting formula serves as an interpolating function to estimate the physical quantity between data points. When two independent variables are used, the result is the equation of a surface that allows objective determination of the isopleths. In a typical meteorological application, objective analysis could be used to derive from scattered observations an expression for contour height as a continuous function of latitude and longitude for the purpose of generating a weather map.