The invention relates to a cooling panel assembly (2) for a wind turbine tower (1). It is arranged to be mounted on such a tower (1) on a section thereof as seen in the circumferential direction. The cooling panel assembly (2) includes at least one cooling panel (2a,2b). According to the invention, the cooling panel assembly (2) includes deflector means (6) mounted at the top of the at least one cooling panel (2a, 2b) such that the deflector means (6) shields the cooling panel assembly (2) from above. The deflector means (6) has substantially the same circumferential extension or more as the other parts of the cooling panel assembly (2). The invention also relates to a wind turbine tower (1) provided with at least one such cooling panel assembly (2).