Abstract: An air cooled condensing tower system has a framework supporting a fan deck, a plurality of steam headers running longitudinally above the fan deck, a plurality of condensing coils extending downward and at an angle from the steam headers, and above the fan deck, a plurality of collector tubes disposed at the bottom of the condenser coils and above the fan deck. At least one substantially non-porous side wall is disposed on at least one side of the tower spanning from a height generally proximate the steam supply headers downward to a height generally proximate the fan deck. A downwardly and outwardly projecting substantially non-porous elongated upper air guide extends downwardly and outwardly from the side wall.