This study investigates the different effects of the geometry, orientation and layout of two adjacent tall buildings on the surrounding microclimate conditions using a combination of computational fluid dynamics (CFD) simulations in Ansys Fluent software and microclimate modeling in Envi-met software. In addition, field measurements of air temperature, relative humidity, and wind speed were conducted under different weather conditions to validate and complement the simulations, providing a more robust assessment. Unlike most previous studies that focused on single tall buildings, this study uniquely examines the combined aerodynamic and microclimate effects of two adjacent tall buildings with different orientations and the same height in a real semiarid context. The findings show that building orientation and shape strongly affect wind speed, temperature, and humidity. One building produced wind speeds about three times higher, creating corridor effects and thermal fluctuations (-2.30 to + 0.35 K/h). The other generated weaker airflow but a steadier cooling trend with variable humidity. Simulations also revealed stagnation zones with high humidity behind buildings and drier conditions on windward sides. Overall, high wind speed alone does not ensure pedestrian comfort; instead, geometry, orientation, and height interact to determine whether airflow improves ventilation and cooling or promotes heat and moisture buildup. These results highlight the need to integrate aerodynamic and microclimatic responses into tall building design, offering guidance for climate-responsive urban planning in semi-arid cities.