Gliding snow

Characteristics

• The entire snowpack glides over the ground, typically on smooth ground such as grassy slopes or smooth rock-zones.
• High glide-snow avalanche activity typically results from a thick snowpack with no or only few weak layers.
• Glide snow avalanches can occur with both a cold dry snowpack and a warm wet snowpack.
• The release of a glide-snow avalanche is difficult to predict, although glide cracks open usually before a release.

Spatial distribution

• Predominant on smooth ground (rock or grass) and on every aspect.
• Varying steepness.

Trigger mechanisms

• Glide-snow avalanches are caused by a loss of adhesion at the snow / ground interface.
• The snowpack is gliding due to gravity.

Location of weak layer in the snowpack

Avalanches release at the snow/gruond interface.

Duration

• Days to months; occasionally during entire winter season.
• The release can occur at any time of day or night.
• In the spring, glide-snow avalanches occur most often during the latter part of the day.

Identification of the problem

• With the presence of glide cracks the problem can often be localized; however, they do not indicate imminent avalanche release.
• Avalanche release timing is nearly impossible to predict.
• Avalanche release without pre-existing glide cracks is also possible.