Avalanche

Avalanche is a rapid movement of snow down a slope triggered either naturally or by human activity. This occurs typically in mountain terrain. Avalanches are divided into four classes:
1. Dry powder avalanches
2. Wet new snow avalanches
3. Snow slabs or Wind slabs and
4. Wet old snow avalanches.

Avalanches are river like speedy flow of snow or ice descending from the mountain tops. Avalanches are very damaging and cause huge loss to life and property. 

In Himalayas, avalanches are common in Drass, Pir Panijat, Lahaul-Spiti and Badrinath areas. As per Snow and Avalanche Study Establishment (SASE), of Defence Research and Development Organisation (DRDO), on an average around 30 people are killed every year due to this disaster in various zones of the Himalayas. Beside killing people, avalanches also damage the roads and others properties and settlements falling in its way. 

Area Prone to Avalanches

Avalanches are common in Himalayan region above 3500m elevation.

Very frequent on slopes of 30-45°.

Convex slopes more prone to this disaster.

North facing slope have avalanches in winter and south facing slopes during spring.

Slopes covered with grass more prone to this hazard.