When new snow falls, the snowflakes need time to join together and to the surface on which they have fallen. Until then, the snow is unstable and there is a higher risk of avalanches occurring. The length of this process depends very much on the temperature. the colder it is, the longer it takes for the new layer of snow to become stable. At 0°C(32°F), the snow first becomes stable after four to five hours. At -5°C (23°F), it takes eight to ten days for snow to become stables. At -25°C(-13°F), the snow is only stable after three to four weeks. It is important to remember, that even if it is only minus two degrees outside the ski hut, it may be minus eight degrees up in the mountains where the avalanches begin.