The analysis was based on hourly values of the immission of sulphur dioxide, nitrogen dioxide and suspended particulate matter PM10, and on data involving meteorological elements gathered at 3 measurement stations in Szczecin in January and July, 2006. It was observed that the quantity of the immission of essential air impurities in the area of Szczecin agglomeration in January and in July, 2006, were differentiated by anemometric conditions. The direction of wind decided about the inflow of impurities, whereas wind speed increase caused a decrease in their concentrations. The role of wind velocity as a factor of dispersion was observed first of all with regard to the immission of nitrogen dioxide in July. The air quality in Szczecin in January, 2006, was mainly determined, apart from the anemometric conditions, by temperature and relative temperature of the air, increase of which resulted in a decrease in immission. Non-typical weather prevailing in January, 2006, determined more strongly the concentrations of suspended particulate matter PM10, while in July – those of nitrogen dioxide. The effect of meteorological conditions on the concentrations of nitrogen dioxide was, in both months, larger in the suburban parts of Szczecin, and smaller in the centre of the city.