A prototype of an air quality forecasting system (AQFS) on a turbulence-permitting (TP) horizontal resolution of 50 m is developed. AQFS is based on the WRF-Chem model and uses high-resolution emission data from different pollution sources. A simulation case study of a typical winter day in south Germany serves as a test bed. Results indicate that the complex topography plays an important role for the horizontal and vertical pollution distribution over the Stuttgart metropolitan area.