Spotting Avalanche Danger
We’re all anxious to get out there on the big hill. It feels like we spend most of the season waiting. We wait for snow to fall, work to be over, and buddies to join. We get it, it’s hard to wait; but waiting one more minute might just save your life. We recommend taking a second to become aware of the telltale signs of avalanche danger.
We’ve got some bad news for you fresh powder lovers. New Snow is a key sign in understanding avalanche risk. 90% of human-triggered avalanches occur in fresh snow. Be extremely cautious the first 24hrs after a storm; avoid risk areas and check avalanche forecasts.
Signs of Recent Avalanche activity are obvious indicators that avy danger should be taken very seriously. If you see signs of recent activity (crown lines & avy debris) take extra precaution. Take note of the elevation, direction, and slope of any hill that has recently slid; there is a high potential for slides to occur on similar hillsides.
Snowpack is composed of a series of layers created with each snowfall. Avalanches occur as weak base-layers collapse and crack. If you see or hear Collapsing or Cracking in the Snowpack you are in danger. You will often feel the snow collapse beneath you, see surface cracking, and/or hear a whomping sound.
As you shred the backcountry you probably head straight for the hills; you might think, “the steeper the better”. We recommend taking a quick minute to survey the scene before you hit the slopes. A couple of minutes has the high potential to save a life. So, make time to analyze avalanche danger before you find yourself buried in it.
Local Indicators include:
Steepness/Slope:
The majority of avalanches occur on slopes between 30 and 45 degrees. Avalanches rarely happen on slopes lower than 30 degrees and slopes above 50 degrees typically sluff as they tend to not build into major slabs. Slopes within 35 and 40 degrees are the “bulls-eye” — most likely to slide.
Wind:
Weather conditions can significantly increase avalanche dangers within the course of a day; one of these conditions is wind. If you come across a slope that has recently wind-loaded you play it safe and stay away. When slopes become wind-eroded, be mindful about where that blown snow has been deposited as the surface will be unstable.
Sun & Temperature:
Another weather condition that can affect snow stability is the sun and its direction. The direction a slope faces becomes a critical indicator of avalanche danger. During mid-winter, north-facing (shady) slopes become more prone to slide and create avalanches. In the springtime, however, watch for wet (melting) avalanches occurring on south-facing slopes. Changes in temperature can dramatically alter the potential of a slope to slide. Take extra precaution on the first warm day after a storm
Before you even consider leaving your home to hit those hills, you should be aware of and take the needed time to look over your local avalanche advisories. These advisories are generated with weather data and on-the-ground research from avalanche professionals, experts, and riders. Avalanche information is thorough and can make the difference in life and death.
Avalanche advisories are represented with visual aids, such as the Avalanche Danger Rose shown to the left. Advisories are generally broken down into 5 danger levels — extreme, high, considerable, moderate, and low. Most avalanche accidents occur in areas rated as “considerable” or higher.
