This presentation will focus on the evolution and variability of moisture and wind in the boundary layer when frontal and/or convergence boundaries (e.g. bores, dry lines, thunderstorm outflows etc) were observed. The goals are to characterize the processes of convective initiation in association with drylines under different weather regimes, and to advance our understanding of the evolution of boundary layer during drylines that determine convective initiation. In particular, we focus on the sensitivities of convection and dryline structure with respect to the water vapor moisture. Two numerical studies during the IHOP_2002 are being conducted using the WRF model. The grid resolutions for both cases are 4 km with 1 km nested domains. The initial and boundary conditions are derived from the ETA model data. Additionally, the high resolution model simulation data provides an opportunity to compare model output and Lidar-based products as well as the in situ measurements in the IHOP domain. Results from this study will be compared with past findings and/or hypothesis made of convective initiation and dryline water vapor mixing ratio variations.