The use of Unmanned Aerial Vehicles (UAVs) as Aerial Base Station (ABSs) is emerging as an effective technique to provide high capacity wireless networks to ground users. In this paper, cell coverage of a low altitude UAV is investigated for supporting such networks. An analytical framework for cell coverage area of an ABS is provided for Suburban, Urban and Urban high rise environments using a solid angle approach including radio link propagation effects in air- to-ground channel obtained from ray tracing simulations. Here, we account for the change in Euler angles such as roll, pitch and yaw due to perturbations by wind gusts or intentional maneuvers which leads to an increase in the geometrical coverage area by approximately 40-50 %, given same transmission power and antenna gain of the ABS.