Abstract The mass flux based subgrid-scale parameterization technique of Gidel (1983, J. geophys. Res. 88, 6587–6599) is re-examined for use in Eulerian long-range transport models. Specifically, the parameterization scheme is incorporated into the STEM-II Eulerian transport/transformation/removal model and the model is used to investigate pollutant transport in a nonprecipitating cumulus cloud ensemble. The effects of entrainment, detrainment, evaporation and the transport by subsidence, updrafts and turbulent diffusion are included in the analysis. Presented simulation results indicate that the parameterization is able to treat the rapid vertical transport by cloud updrafts, enables the calculation of reaction rates based on subgrid-scale concentrations, and is readily adopted by Eulerian models.