Calculations made for September 2011 and 2021 using the regional model WRF-Chem. Initial and boundary conditions for the distribution of gas component concentrations were set using the results of the calculations from two global chemical transport models. The model used for 2011 was MOZART4, and for 2021 | WACCM. As a result, it was shown that for 2011, the model accurately reconstructs the average daily values for carbon monoxide and ozone concentrations. The concentrations of nitrogen oxides and sulfur dioxide shows quality agreement of the time course. For 2021, the model shows underestimated values for both carbon monoxide and sulfur dioxide; and, conversely, overestimated concentrations for ozone and nitrogen oxides.