Online Avalanche Course

This course is a beginner's guide to avalanche forecasts, danger scales, danger types, and some of the mitigations available to those heading into the backcountry. We highly recommend you take the necessary avalanche rescue equipment (Shovel, Transceiver, Probe)  and seek out specific training on avalanches and backcountry travel.

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How to Use The NZAA Website

The Danger Scale

"This is the scale produced by a joint U.S. Canadian committee, the North American Avalanche Danger Scale Project (NAADSP) published in the fall of 2010. It has also been adopted by all English-speaking countries. Understanding the New Zealand danger will help you make more informed decisions on route select and terrain choices, based on the days forecast danger level.

The danger scale will give you four important bits of information. Firstly the danger level; the danger level is assigned a word and colour which reflect the likelihood of trigger and the destructive size of the avalanche. This gives a broad overview and the specifics are discussed in the following boxes. Based on the forecast avalanche danger level travel advise is given. This travel advise gives tips on terrain features to avoid and insights into the spatial distribution of the avalanche problem. Finally avalanche likelihood, size and distribution are in the last two boxes. This will not only tell you how likely a human-triggered avalanche is but also the destructive size and spatial distribution of likely avalanches. All this information should greatly influence your route selection and decision making not only on the slopes but well before you even step foot in avalanche terrain."

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Avalanche Problems

Avalanche danger is a broad overview of the avalanche forecast. Avalanche problems are an extension of this to help you understand the type of avalanche you may encounter and how you can best avoid them. In the avalanche forecast, avalanche problems are found just below the elevation band danger ratings. There can be up to three avalanche problems listed and they are described by avalanche character, location, size, and likelihood of trigger.

Lets quickly touch on each one

  • Avalanche characters: This is a description of the kind of avalanche you are most likely to encounter throughout the day. This describes one of eight possible avalanche types; all of which have different characteristics and should influence your travel choices. The avalanche character is displayed on the top left of the avalanche problem sections.
  • Avalanche Location:  On the NZAA this information is displayed on the avalanche danger rose. This diagram tells you not only the aspect you are most likely to encounter avalanches on but also the elevation. Picture this diagram as a 3D mountain with the outer section being the base of the mountain and the central rose being the summit. The 'rose' allows you to understand where and what elevation you can expect to encounter that specific avalanche character.
  • Likelihood: The likelihood of triggering an avalanche can change day to day and even hour to hour. This is shown on a graph with the lower sections having a lower likelihood and the upper section having a higher likelihood. The likelihood is described by the words unlikely, likely and almost certain.
  • Size: Much like likelihood, size of an avalanche is also shown on a bar graph. The size is described using the words smallest to largest and reflects the destructive size scale. If you are unaware of the destructive size scale check out our free online avalanche course.

Combing these four avalanche 'problems' describes the avalanche danger in far more detail, telling you what type of avalanche to expect and aspect and elevation you should expect to encounter it on and finally the likelihood and size of the triggered avalanche. Combing all four problems will help you to make informed decisions on where and when to travel in avalanche terrain.

Forecast Page FAQ

How often are they updated? 

During the forecast season, the NZAA is updated daily by a highly experienced team of forecasters around the country. During certain conditions, the NZAA forecasts are updated several times during a day. It always pays to refresh the forecast closer to the time you're heading out.