The basics of avalanche formation and avoidance

03.03.2025

Avalanche awareness for beginners: Understand the basics of avalanche formation and learn how to protect yourself effectively.

Introduction to avalanche awareness

Avalanches are one of the biggest risks for skiers, ski tourers and freeriders in alpine terrain. In order to be safe when travelling, it is crucial to understand the basics of avalanche formation. In this article, we will shed light on the physical processes that lead to avalanches and give you valuable tips on how to avoid them.

What are avalanches?

An avalanche is a sudden and rapid movement of snow that usually slides down a steep slope into the valley. These natural phenomena can be triggered by a variety of factors, including weather conditions, the nature of the snowpack, the terrain and human activity. In the Alps, one of the most visited mountain ranges in the world, avalanches are a serious risk for winter sports enthusiasts.

Types of avalanches

There are different types of avalanches, which differ in their formation and behaviour. The most common and most dangerous types of avalanches for ski touring, freeriders and skiers are the following:

Slab avalanches: This type of avalanche occurs when a continuous layer of snow slides down an unstable layer. They are often the most dangerous as they can carry large amounts of snow and move quickly. Slab avalanches account for around 90% of avalanche accidents.
Wet avalanches: These avalanches occur when the snow becomes damp due to a rise in temperature or rain and loses stability. They move more slowly than slab avalanches, but can also be dangerous, especially in spring when the weather is changeable.
Dust avalanches: This type of avalanche consists of fine, pulverised snow moving in a cloud. Dust avalanches are less common, but can be extremely dangerous as they can spread very quickly and cover large areas.

The factors of avalanche formation

The formation of an avalanche depends on several factors:

Snow cover: The structure and stability of the snow cover are crucial. An unstable layer can be caused to slide by additional loads, such as skiers or fresh snow.
Amount of snow: A sudden and massive amount of fresh snow that falls in a short period of time can significantly increase the risk of avalanches. If a thick layer of snow is deposited on top of the existing snow cover, this can lead to unstable snow conditions. This instability increases the risk of avalanches forming and sliding.
Weather conditions: Temperature changes, precipitation and wind influence snow conditions. A sudden rise in temperature, for example, can jeopardise the stability of the snow cover. The following article provides further information on wind as a master builder of avalanches.
Terrain: Steep slopes are particularly at risk. Knowledge of the geography of the surrounding area is crucial for identifying potential danger zones.
Human influences: Human activity, such as skiing in certain areas or skiers triggering avalanches, can also contribute to the formation of avalanches. It is important to be aware of your own responsibility.

Tips for avoiding avalanches

To minimise the risk of being caught in an avalanche, you should take the following measures:

Keep informed: use weather and avalanche reports to find out about the current situation. Websites such as the avalanche warning service provide valuable information and up-to-date warnings. Also use appropriate apps.
Equipment: Always carry an avalanche transceiver (avalanche transceiver), a shovel and a probe. This equipment can be crucial in an emergency.
Share your plans: Inform friends or family about your planned tours and/or the apps you are using. In an emergency, this can be crucial for providing help quickly.
Group behaviour: Don't ski alone and keep your distance from other skiers to reduce the risk. Discuss in advance how you would act in an emergency.
Route selection: Choose your routes carefully. Avoid steep slopes and areas that are considered at risk of avalanches. Use maps and apps to plan safe routes.
Observe the snow conditions and terrain: Look out for signs of avalanche danger, such as cracks in the snowpack or the sound of falling snow. These signs may indicate an unstable snowpack.
Training: Take part in avalanche courses to deepen your knowledge of avalanche formation and avoidance. Many organisations offer special training courses to help you better understand the dangers.
Follow the weather development: Pay attention to weather forecasts and their development during your tour. Weather conditions can change quickly and have a significant impact on the avalanche risk.
Behaviour in case of suspected avalanche danger: If you have the feeling that the avalanche danger is high, you should reconsider your plans. It is better not to go on a tour than to expose yourself to unnecessary risks.

Safety first

Knowing the basics of avalanche formation and avoidance is essential for anyone travelling in alpine terrain. By being properly prepared and understanding the dangers, you can significantly increase your safety and that of your companions. Remember that while the mountains are beautiful, they also require respect and caution. Enjoy your time in nature, but do so wisely and responsibly.