How to read the avalanche forecast

The avalanche forecast describes the avalanche danger using both text and symbols. Read more about how to interpret and understand the forecasts. The forecasts are structured to present general information at the top with a more detailed description of the avalanche danger for the area further down.

In the forecast, you will find a score for the avalanche danger, assessments of which are the most dangerous parts of the terrain and which type of avalanches currently pose the biggest problem. It also provides advice on how to go out travel in the mountains without being exposed to unnecessary risks. Bear in mind that the avalanche forecasts describe the avalanche danger in general terms over a large area and there may be some local variations.

The avalanche danger in the area

At the top, you will find the avalanche danger in the area expressed according to the international avalanche danger scale. (Scored from 1 to 5) Each step on the scale has an icon, a name in text and a standard recommendation. The assessment applies to the parts of the mountains specified in the avalanche problem block. That means that the avalanche danger may be lower in parts of the terrain, for example on slopes facing in a certain direction or at a certain elevation.

Heading recommendations

This is the section in which our forecasters write a short text on the avalanche danger every day and provide recommendations for anyone planning to be on the mountain in the area.

Heading trend

This contains a description of how the avalanche danger is expected to develop over the next few days. The avalanche danger is also scored for days two. Bear in mind that forecast becomes more uncertain the further ahead you look and ensure that you use the latest forecast as far as possible. The accuracy is extremely dependent on the accuracy of the weather products that the avalanche forecast is based on.
If the weather forecast is uncertain and has a significant impact on the avalanche danger that is stated in the text.

About the different avalanche problems

The section on the avalanche problem is an important section for planning tours and making a choice of route when you are on the mountain. The section contains information on which "type of avalanche" currently poses the greatest danger, a brief explanation of what is causing the avalanches and in what terrain the avalanche problem in question is most common. There are also tips on how to recognise places where an avalanche problem exists. This is done using text and icons. Please note that we sometimes show two different avalanche problems in two different sections.
Learn more about the various types of avalanche at the bottom of the page.

Two icons indicating whereabouts on the mountain the avalanche problem is most common – heights and compass points

Snow conditions and the avalanche danger differ from one place to another on the mountain and the following icons indicate whereabouts on the mountain the avalanche problem is most common. The areas not marked are generally safer places.

Relevant elevation

The figure illustrates at what elevations the avalanche problem exists Avalanche danger can vary with elevation because of the effects that wind, temperatures and precipitation have on the snowpack. The coloured area shows the elevation band where the avalanche problem exists.

Relevant aspect

If the avalanche problem is most common on slopes in certain aspects, it is shown here. Avalanche danger can vary between different aspects because of the effects that wind, temperatures and precipitation have on the snowpack. The figure illustrates in which aspects the avalanche problem exists.

Icons for probability and size of avalanches

These figures illustrate the likelihood of avalanches being triggered and the expected size of these avalanches. Avalanche activity can range from small wind slabs and slides in recent storm snow up to massive events where the whole snowpack release at full depth. The size of the avalanche is a combination of many factors which include both snowpack and terrain characteristics. The consequences tend to get worse as the avalanche size increases.

A low probability but high consequence scenario is particularly tricky to deal with. That means that the likelihood of triggering avalanches is low but if an avalanche releases it will be large with high destructive potential. During these circumstances, the snowpack may appear stable and it is easy to underestimate the risks.

Heading snowpack

This section is only available in swedish. It discusses the snowpack structure and the on-going processes within the snow. It can include information about slabs, trigger sensitivity, weak layers, snow crystals, snow metamorphosis and other technical terms

Heading weather

The weather forecast comes from the Swedish Meteorological and Hydrological Institute (SMHI) meteorologists and applies to an area that is larger than the avalanche forecast area. It is intended to provide an overview

About the various types of avalanches

There are two main types of avalanches: slab avalanches and loose snow avalanches, with slab avalanches causing most avalanche accidents. In the avalanche forecasts, we also describe the avalanche danger based on the "type" of avalanche. In simple terms, the type describes the cause of the avalanche. It can be used to recognise and anticipate where avalanches may occur.

Slab avalanches

Wind slabs

Avalanches in drifted snow are often relatively small but can still be large enough to bury a person. If the main problem is avalanches in drifted snow, it is mainly on the lee side of the mountain that the risk arises, for example on the eastern side of the mountain if the wind is blowing from the west. However, slabs of drifted snow can also be formed on other sides if terrain formations mean that lee and drifted snow are combined at the location. A problem of avalanches in drifted snow is best dealt with by identifying and avoiding the places where snow has gathered in the most recent snowdrift.

Storm slabs

Fresh snow avalanches can range from slides involving small limited slabs to avalanches involving the entire slope. These are a deceptive type of avalanche since the slab itself can appear soft and fluffy. Storm slabs normally stabilise within a few days. Be very careful and make careful choices of route when the avalanche forecast warns of fresh snow problems.

Persistent slabs

These avalanches are caused by the the fact that there are older, weak layers down in the snowpack containing faceted, angular snow with few bonds and low cohesive strength. This also includes surface hoar that has been covered by snow and buried under a slab. Persistent slabs often produce large avalanches involving entire slopes and these avalanches often fracture above the place where you are standing. It is sometimes even possible to remotely trigger them from connected lower angled terrain.

Both faceted snow and surface hoar can remain under the snow surface for weeks or months. Natural avalanche activity takes place primarily when the snowpack is subjected to changes, mainly in the case of large snowfalls and strong winds, but it can also occur during rapid temperature rises. It takes significantly longer for persistent slabs to stabilise between snowfalls than it does for storm snow. This means that people can often trigger avalanches a long time after the last snowfall when the avalanche forecast mentions persistent slabs.

If the avalanche problem is "persistent slabs large safety margins in the choice of route and good group management are particularly important. It is extremely difficult, if not impossible, to know exactly which slopes the weak snow layer is buried in. Treat all steep slopes as potential avalanche slopes even if all the visible signs indicate that they are stable. Be very careful when you cross areas where the snowpack goes from thin to thick. It is easier to trigger the avalanche where the snowpack is thin and, once the fracture in the snowpack has occurred, it can spread to the thicker snow slab and the avalanche can become very big.

Wet slabs

Wet slab avalanches occur when one or more layers in the snowpack reach 0 degrees. The rise in temperature can result in wet slabs in the upper part of the snow or very large destructive events where the whole snowpack release from the bottom of the snowpack or the ground. Such avalanches are very dangerous and can easily cause damage to forest and buildings. Avoid avalanche terrain when the snow begins to become wet due to sunshine or rainfall. Depressions and gullies that form natural points for collection of melt water are particularly vulnerable. Be particularly careful when the snow does not re-freeze at night.

Loose snow avalanches

Loose dry avalanches

Loose dry avalanches are usually small but in extreme cases they can become big if the slope is long and steep. They start in very steep terrain and rarely occur more than a few days after a snowfall. Loose dry avalanche problems are rare in the forecast. If we do issue such warnings, it is best to avoid very steep slopes for a few days to give the new snow time to stabilise. This is particularly true where there are terrain traps, i.e., places where the consequences of an avalanche become particularly severe.

(Read more about terrain traps here).

Loose wet avalanches

Loose wet avalanches have greater destructive power than loose dry avalanches and occur mostly on steep sunlit slopes. They often only occur on afternoons when the sun has melted the surface snow. The easiest way to avoid wet snow avalanches is to avoid going on steep southern-facing slopes in the afternoon when the sun has heated up the snow. Keep an eye on the night-time temperature. If the snow does not re-freeze overnight, avalanches of this kind can occur at any time of the day or night. Wet avalanches travel a long way so you need to be aware of potential overhead hazard even in low angle terrain.