Winter Sports · Advanced · Snow and mountain science
How to Read an Avalanche Bulletin: Danger Levels and Limitations
An avalanche bulletin is a daily forecast showing the avalanche danger in a region on a scale from 1 to 5, on which aspects and elevations it is expected and with which avalanche problem. In Europe the scale is set by the European Avalanche Warning Services (EAWS): 1 low, 2 moderate, 3 considerable, 4 high, 5 very high. The level is based on how unstable the snowpack is, on how many slopes this is found and the size of the largest expected avalanche. An important detail: according to data from the Swiss Institute for Snow and Avalanche Research (SLF) and the EAWS, about half of avalanche deaths occur at level 3 (considerable), because this level is issued often and people underestimate the danger. The bulletin is a regional forecast; it cannot tell you the situation on a single slope and does not replace an on-site assessment. In Türkiye, no daily regional avalanche bulletin with levels 1–5 is published; for Bansko, the Bulgarian Avalanche Association publishes a bulletin.
An avalanche bulletin is a daily forecast summarising the avalanche danger in a region. Bulletins in Europe use a common structure:
Danger level (1–5), and different levels for different elevations where needed.
Aspect-elevation rose: Which slope aspects the danger applies to, and above or below which elevation.
Avalanche problems: New snow, wind slab, persistent weak layers, wet snow or gliding snow.
Snowpack and weather description: The reason for the situation, in a short text.
We explain how avalanches form and the five avalanche problems in our guide How Do Avalanches Form?
The European avalanche danger scale
There is no official Turkish translation of the EAWS scale; the descriptions below summarise the EAWS's English definitions.
Level
Name
Summary of the EAWS definition
1
Low
Triggering is generally possible only from high additional loads in isolated areas of very steep, extreme terrain. Only small and medium natural avalanches are possible.
2
Moderate
Triggering is possible, primarily from high additional loads, particularly on the steep slopes indicated in the bulletin. Very large natural avalanches are unlikely.
3
Considerable
Triggering is possible even from low additional loads. In certain situations some large, and in isolated cases very large, natural avalanches are possible.
4
High
Triggering is likely, even from low additional loads, on many steep slopes. In some cases numerous large and often very large natural avalanches can be expected.
5
Very high
Numerous very large and often extremely large natural avalanches can be expected, even in moderately steep terrain.
A high additional load is a large load such as a group of skiers or a person falling; a low additional load is a single skier or walker.
How is the level determined?
The EAWS uses a matrix so that forecasters assign the level consistently. The matrix has three inputs:
Snowpack instability: How easily does it fracture?
Frequency: On how many slopes is this the case? Isolated spots or many slopes?
Avalanche size: How big is the largest expected avalanche?
The European scale has been in use since 1993; the matrix was updated in 2025, and the scale itself is also under review (Müller, Techel and Mitterer 2025).
Sub-levels: 3− and 3+
Some bulletins (for example the Swiss one) subdivide each level from level 2 upwards with −, = and +. The SLF's warning is clear: “3−” is still level 3.
Why is level 3 the most dangerous?
Level
How often is it issued in winter?
Share of avalanche deaths
1 Low
About 20%
About 5%
2 Moderate
About 50%
About 30%
3 Considerable
About 30%
About 50%
4 High
A few days
About 10%
5 Very high
Very rarely
About 1%
According to the SLF, the risk increases about four times with each level; at level 3 the risk is about 17 times that at level 1. At levels 4 and 5, people generally do not go into the mountains; level 3, however, is both issued often and perceived as “just above moderate” and underestimated. That is why about half of the deaths occur at this level.
Avalanche sizes
Size
Name
Length
Volume (approx.)
What does it mean?
1
Small
10–30 m
100 m³
Unlikely to bury a person, but can knock them over
2
Medium
50–200 m
1,000 m³
Can bury, injure or kill a person
3
Large
Several hundred m
10,000 m³
Can bury and destroy cars and wreck small buildings; very high likelihood of serious consequences for a skier caught in it
4
Very large
1–2 km
100,000 m³
Can bury trucks and trains; can reach the valley floor
5
Extremely large
More than 2 km
More than 100,000 m³
Can devastate the landscape; the largest known avalanches
Even a “medium” avalanche is enough to bury a person; the phrase “small avalanche” does not mean safe.
The aspect-elevation rose
The rose-shaped (compass-like) diagram in the bulletin shows which slope aspects (north, north-east, east…) the danger applies to and above which elevation. For example, the phrase “north-west to east-facing slopes above 2,200 metres” means that on these slopes the danger is higher than in the region in general. To recognise these slopes in the terrain, you need a map and compass or a compass app on your phone.
What the bulletin cannot tell you
The limitations the SLF emphasises:
The bulletin is a regional forecast; it cannot know the situation on individual slopes. It does not replace an on-site, local assessment.
The recommendations in the bulletin are for people outside the secured areas of the ski resort. The safety of open, marked pistes is managed by the ski resort; here, respecting closed-piste and piste-boundary markings is the most important rule.
Level 1 does not mean “no risk”. About 5% of avalanche deaths occur at this level.
Which bulletin where?
Region
Bulletin
Note
Türkiye
No daily regional bulletin with levels 1–5
The meteorological service (MGM) and the disaster management authority (AFAD) announce avalanche risk as text within weather and disaster warnings; Türkiye is not an EAWS member
Bulgaria (Bansko)
Bulgarian Avalanche Association, report.avalanche.bg
Uses the EAWS 5-level scale; Pirin (Bansko), Rila and Vitosha regions
Georgia (Gudauri)
Avalanche Georgia, avalanche.ge
A volunteer association; daily forecast for Gudauri throughout the winter
The Alps
National official services (e.g. SLF), avalanches.org
Being able to read the bulletin means understanding the warnings on the mountain and decisions to close pistes, even for a skier who stays on the pistes. On an activity holiday spent at the same resort for several days, you can apply this knowledge every morning to the signs and the map. Doğadayız winter packages include accommodation, ski pass and equipment. Talking through the day's weather and piste conditions with the group over breakfast is part of a social adventure holiday. For programmes, see our winter activity holidays page.
Doğadayız Packages
Doğadayız packages for your level
Winter activity holidays with accommodation, ski pass and equipment included, shared with a group.
The easiest way to learn to ski: a winter activity holiday
An activity holiday puts a sport at the heart of your trip: transport, accommodation and meals are planned, so you can focus on learning on the slopes. On Doğadayız winter activity holidays, accommodation, ski pass and ski or snowboard equipment are included in every package; course packages include basic lessons with instructors affiliated with the Turkish Ski Federation, while experience packages let you practise on the slopes at your own level.
What makes the programme different is the group: sharing the slopes with people at a similar level, dinners and nights out together, and a group leader by your side at all times. Solo travellers become part of this social adventure holiday from day one. That is why we describe our programmes as a social adventure holiday.
The scale of the European Avalanche Warning Services (EAWS) has five levels: 1 low, 2 moderate, 3 considerable, 4 high, 5 very high. The level is determined by the instability of the snowpack, on how many slopes this is found and the size of the largest expected avalanche.
At which level do most avalanche deaths occur?
According to SLF and EAWS data, about half of avalanche deaths occur at level 3 (considerable). This level is issued about 30% of the time in winter and the danger is often underestimated; the risk is about 17 times that at level 1.
Is there an avalanche bulletin in Türkiye?
In Türkiye, no daily regional avalanche bulletin with levels 1–5 like those in Europe is published; MGM and AFAD announce avalanche risk within weather and disaster warnings. For Bansko, the Bulgarian Avalanche Association publishes a bulletin using the EAWS scale.
An avalanche is snow on a slope suddenly sliding and flowing downhill. The great majority of fatal avalanches are slab avalanches: there is a weak layer inside the snowpack; the cohesive layer of snow above it (the slab) fractures on this layer under a load, and a wide area breaks away at once. According to the Swiss Institute for Snow and Avalanche Research (SLF), more than 90% of avalanche deaths are caused by slab avalanches. A dry slab avalanche generally needs a slope of at least 30°; the slope angle where human-triggered avalanches start averages around 38–39°. The main factors that increase the risk are new snow, wind-drifted snow, temperature changes and persistent weak layers in the snowpack (surface hoar, faceted grains, depth hoar). The European Avalanche Warning Services (EAWS) group these situations into five typical avalanche problems.
Marked and open slopes are secured against avalanches; off-piste terrain is not, and skiing there is entirely at your own risk. Even in Türkiye, skiers who went off-piste have lost their lives in avalanches: at Erciyes in 2022 and at Palandöken in 2024. If you are thinking of going off-piste, there are three conditions: reading the avalanche bulletin (on the European scale of 1–5; about half of deaths happen at level 3), everyone in the group carrying a transceiver, probe and shovel, and having learned to use them through training. A buried person's chance of survival is above 90% in the first 10–18 minutes but drops sharply after that; the rescue is up to the friends you are with.
A whiteout, as defined by the American Meteorological Society, is an optical phenomenon in which the observer appears to be engulfed in a uniformly white glow: over unbroken snow cover under a uniformly overcast sky, shadows, the horizon and clouds disappear, and the sense of depth and direction is lost. According to the UK Met Office, the risk increases when fog or mist combines with widespread snow cover. When skiing, this means not being able to see the gradient, the bumps or the edge of the slope. When visibility worsens, slow down, stay on the marked slope near the markers along its edge, and switch to a slope one level easier; if visibility is very poor, ski down to the nearest lift station and call it a day.
