Performance of a Heller cooling tower under wind conditions has been investigated by measuring wind velocity and its direction around the tower and inlet and outlet water flow rates and temperatures. Results show that air suction at the tower prevents flow separation at its periphery. The tower front cooling sectors experience better airflow distribution compared to sectors parallel to wind direction, which improves their thermal performance by about 20% compared to still-air conditions. Airflow pattern around the tower at different distances shows that wind tangential velocity at corner sectors is four times the velocity at the reference point, decreasing air pressure and tower suction.