Vortex shedding topology and its influence on the pressure dynamics for large aspect ratio buildings under the atmospheric boundary layer inflow conditions are studied. A numerical study using large eddy simulation (LES) is conducted on two rectangular high-rise buildings with different blockage ratios with divergence-free turbulence generator. Two flow visualization techniques, namely phase averaging and dynamic mode decomposition (DMD), are employed to extract the spatial patterns of the velocity field and the pressure field around the vortex shedding frequency. For the phase-averaging technique, the importance of applying a reliable vortex shedding frequency detection algorithm is discussed in detail and the result is compared with the fixed-frequency-method. Phase-averaged velocity and pressure contours based on the stationary and convective reference frame are presented and analyzed as part of the investigation. For the DMD technique, a parametric study is performed on the number of snapshots and delay embedding length. The two techniques result in similar patterns. By establishing this visualization, the study assists in comprehending the dynamics of the flow field and its alterations in response to changes in building geometry. Additionally, it sheds light on how these dynamics impact the surface pressure on each wall.