In this study, a simple methodology is proposed to estimate ambient temperature bin data. The proposed model is based on the determination of the best fitting equation describing the characteristics of the cumulative frequency distribution of yearly bin weather data values. This approach makes it easy for anyone, who needs bin data values for any location, to adopt the fitted equations in the building energy performance calculations. A case study was applied to six cities in Turkey, and the applicability of the proposed model has been shown. The obtained R-2 values of the fitted equations are higher than 0.99. Therefore, the coefficients of the fitted equations for any location can be used easily to predict any bin data value to be used in building energy performance calculations. The results of this study are important for the experts using bin method.