The goal of this project is to explore the atmospheric boundary layer evolution during down-valley and downslope flows over the Las Vegas valley. The study will have two main efforts: 1) evaluate the three primary PBL closure schemes in the WRF model (Mellor-Yamada-Janjic, Yonsei University, Quasi-normal Scale Elimination) and quantify model biases at a fine spatial scale configuration; 2) evaluate the different terrain averaging and filtering/smoothing schemes in the WRF model, as well as the feedback of a nested domain using one-way versus two-way nesting simulations to quantify their impact on near-surface forecast results.