Mountain tops are commonly the windiest places, and the Cairngorm mountains are no exception. Gales are common. Records from the anemograph on the summit of Cairn Gorm show that the strongest gusts recorded annually occurred between 1979 and 1987, ranging from 177 to 275 km/h. Prevailing winds are from the south-west. Still days are associated with anticyclonic conditions.
Local valley winds (anabatic and katabatic ) are also important. Coire Cas appears to develop a wind funnel effect when winds are south-easterly. In spring and early summer, anticyclonic weather develops convection currents, which in turn cause strong katabatic winds to blow down the hillslopes into the glens. When it is snowing, blizzard-like conditions result.
During spring and early summer, it can be calm in the valleys but a fohn-like wind blows down the lee slopes of the higher hills and moors.
Exposure to wind has important impacts on vegetation, both physical (krumholz effect) and ecological. It also has important implications for human activity in the mountains, notably the ‘windchill’ effect, especially on the high tops with little, if any, shelter.