The area around Squamish is a winter wonderland but its also a place where you must remain ever vigilant to possible dangers. Whether you go snowboarding, skiing, snowshoeing or climbing, you must always be conscious that avalanches can and do happen no matter what your experience.
What is an Avalanche?
A powerful act of nature, an avalanche has the potential to travel a 120 mph. The sheer force of the flowing snow knocks down trees and pushes boulders. It can easily sweep you away so you are either buried or pushed over a cliff. If you become buried in the avalanche snow mass, you will effectively be encased in a frozen tomb because the friction of the powder as it flows at rapid speeds causes it to melt ever so slightly. When the snow finally stops all movement it rapidly refreezes into an ice shell that is virtually impossible to dig out from under. Unfortunately, most people cannot survive beneath the snow for more than 30 minutes so it is imperative that you carry an avalanche transceiver to call for help.
The Best Avalanche Defense
The best defense against becoming a victim of an avalanche is to know the snow conditions in the area you plan on visiting. You should make your decisions on how to play safe or not to play at all depending on the regional forecast.
- Avalanche Canada has updated and informative forecasts for the Sea to Sky region here : https://www.avalanche.ca/forecasts/sea-to-sky
- You can also crowd source information from facebook groups like this one: https://www.facebook.com/groups/southcoasttouring
Contributing Factors to an Avalanche
You should always pay close attention to the terrain around you. A slope angle of 30 to 40 degrees is a dangerous area. A clinometer on a compass or one designed for snowpack is a handy tool to have in the backcountry. Also, remember that a south facing slope tends to be more stable than a north facing slope due to sun exposure. Unfortunately, north-facing slopes are often favored by winter sports enthusiasts because of the soft powder but they are notoriously unstable and dangerous. In the spring or summer, a south facing slope starts to melt and becomes prone towards a wet snow slide. Also, watch for unstable slopes, boulders, and cliff bands which are all dangerous areas. You should always avoid steep, narrow gullies that tend to collect snow and can easily trap you if an avalanche occurs.
- Loose Snow: Loose snow avalanches occur when a hardpack has not formed. They start at or near the surface of the snow and gain momentum as they flow down a slope. They typically create a triangular-shaped descent path. A loose snow avalanche can be triggered by snow clumps falling from trees or cliffs onto the surface of the soft snow. Dry or wet snow are all susceptible to a loose snow avalanche. In warm months, a wet loose snow avalanche usually occurs as a result of either meltwater or rain.
- Slab Avalanche: A slab avalanche happens when a layer of snow breaks free of the snow beneath its surface. This is a common form of avalanche for the backcountry. Snowstorms and strong winds often deposit layers of snow on top of each other that change over time. Some of the layers may become strong but others are weak. The weak layers do not bond with the strong layers and cause the two to separate. A slab avalanche occurs when a trigger disturbs the layer such as a skier or a climber.
Here are several dangerous avalanche conditions:
- Precipitation: Snow becomes unstable after rain or heavy snowfall. If a large amount of snow falls in a short time then it can trigger a slide. Heavy and wet snow are also more prone to sliding. The rain even acts as a lubricant that makes the slide flow faster.
- Wind: High winds upset the snow’s surface and can cause a wind slab slide.
- Temperature: Temperature fluctuations breed snow instability.
- Snowpack: Snowpack, especially on slopes between 30 to 45 degrees, are extremely dangerous due to the layers of snow that can quickly start to slide.
Any time you venture into the great outdoors during the winter months you should always remain aware of the potential danger of an avalanche. . We highly encourage taking avalanche courses and refresher courses each year. Awareness of your surroundings and the weather conditions can help save your life