Abstract <p>Conceptual models of runoff formation used in the operational practice of hydrological forecasts by the Hydrometeorological Center of Russia (for example, the HBV-96 model) and many hydrometeorological services of the world include a simplified parameterization of the snow cover dynamics based on the use of the snow cover melting coefficient, snow water-holding capacity and secondary melt water freezing in case of a return to negative air temperatures. Such a schematization of the process has proven itself well for reliable calculation of the snow water equivalent for subsequent use in calculating the inflow of melt water to the surface of the catchment area and calculating characteristics of river runoff. At the same time, the lack of calculation of snow density and snow depth in the used schematization imposes restrictions on the use of schemes for calculating the depth of soil freezing in hydrological models, which seems extremely important for modeling runoff on rivers of temperate latitudes, that is, for most rivers in Russia. To overcome this drawback, the calculation scheme of the snow cover dynamics model has been supplemented with a parameterization of snow density and its height, which has been verified using Roshydromet snow measurement route data and has shown good and satisfactory quality of modeling the model characteristics. The article presents the basic ideas about the used scheme for calculating snow density and its height, as well as the results of checking the quality of modeling using a large array of observation data from Roshydromet snow measurement routes. The prospects for introducing the considered snow cover formation model into operational practice of forecasting are assessed.</p>