This work investigates the influence of atmospheric temperature and rela-tive humidity profiles obtained from radiosoundings, NCEP-I and ERA-INT reanalysis and GFS-FNL analysis data on the simulated evolution of clouds and convection at Nam Co Lake on the Tibetan Plateau. In addition to differences in moisture, the initial at-mospheric profiles exhibit considerable differences in near surface temperatures that af-fect vertical stability. Our analysis is carried out during two days in summer 2012 us-ing a 2D high-resolution modeling approach with a fully interactive surface model so that surface fluxes react to changes in cloud cover. Modeled convection for the radiosound-ing profile compares reasonably well with weather observations for the first day, but less well for the second day, when large-scale synoptic effects, not included in the model, be-come more important. The choice of vertical profile information leads to strongly dif-fering convection development, translating into modifications of the surface energy bal-ance and of the energy and water cycle for the basin. There are strong differences span-ning one order of magnitude in the generated precipitation between the model simula-tions driven by different vertical profiles. This highlights the importance of correct and high resolution vertical profiles for model initialization.