The purpose of this study is to introduce the validation system of numerical meteorological forecasting models of Nahaja and also a case study of the performance of this system on the temperature parameter in June 2020 in Tehran province. For this purpose, one-month synoptic temperature data at two meters above the ground of Mehrabad, Imam Khomeini and Doshan Tappeh stations (located in Tehran province) were compared with the output data of Nahaja intelligent weather prediction system, and the performance of the model Was evaluated. This evaluation was performed on the model output at 00 and 12 GMT. The results showed that in the study period, the mean of RMSE for the 3 stations studied, in the first to sixth days of the forecast, respectively was 1.725, 1.634, 1.653, 1.720, 1.871 and 2.131, R was equal to 0.959, 0.916, 0.912, 0.894, 0.873 and 0.859, MAPE was equal to 0.481, 0.453, 0.458, 0.470, 0.522 and 0.598, the mean of Bias was equal to 0.769, 0.516, 0.255, 0.072, -0.108 and -0.279 and the mean of STDE was equal to 1.285, 1.324, 1.345, 1.362, 1.400 and 1.520. The results of 2m temperature assessment in the study period for the three synoptic stations, is evidence of proper performance of the model in this section.