Using a 3-D, non-hydrostatic mesoscale Mars atmospheric model with detailed aerosol/cloud microphysics, we show that the formation of discrete afternoon clouds over the Olympus Mons volcano is due to the symbiosis of upslope thermal flow and a lee mountain wave circulation, and that these clouds exhibit complex particle distributions. Furthermore, we illustrate that this and other mountain-induced circulations transport large quantities of dust, water vapor, and water ice aerosol from lower altitudes into the free atmosphere general circulation. Therefore, these circulations are an important part of Mars' net Hadley circulation and climatic forcing.