Due to the proximity of Picos de Europa to the sea; little more than 20 km, and because they are north of the Cantabrian mountain range, as well as their altitude above sea level, all condition the humid air masses affecting the area. When these get to the coast, they lift cloud fronts with the following condensation, which provokes frequent rainfalls.A weather characterised by a high humidity and little light, conditions the weather peculiarities of Picos de Europa. Both, the North and Western winds are the most dominant in the area, as well as the ones causing the presence of clouds and snow on the mountain massifs. The NW ones are those which clean back the atmosphere.The presence of snow is specially accentuated over the winter months, specially from December, but snow patches are not rare at all, staying permanent in many places of Picos de Europa. Avalanches are also -frequent in those areas where the slopes are steeper, so it is dangerous to walk in the mountains under those slopes with a combination of thick snow and sun exposure; one of those routes is the one between "La Vueltona" and "Horcados Rojos", in the Central Massif.