There are three components to surviving an avalanche. The first is preparation. You need to know how to gauge the likelihood of an avalanche, take the proper precautions, and carry with you the proper equipment. The second is knowing what to do if you’re buried under the snow in an avalanche. The third is knowing what to do if you are stranded by an avalanche.
* How to Lessen the Likelihood You’ll Be Caught in an Avalanche
If you’re going to be spending time in the snowy backcountry—skiing, cross country skiing, snowshoeing, snowmobiling, etc.—you need to be aware of the risks of an avalanche, and reduce the chances you’ll be caught in one.
One thing to consider is to take an avalanche class. An outdoor equipment store or ski area would be the best place to inquire about such a class in your area.
Avalanche deaths have occurred every month of the year, so no time is completely safe. But avalanches are not spread out equally throughout the year. The greatest danger in most areas is from January to March, when there is the most snowfall in most mountain areas. There is a mini-peak in avalanche activity in May and June, as snow melts.
You are safer with one or more companions than venturing into the backcountry alone. When you’re crossing a suspect area, spread out. As long as at least one person is out of the path when an avalanche occurs, there is a good chance to rescue the person or persons who might be buried.
A big factor in avoiding avalanches is being aware of the red flags that nature provides.
Heavily forested areas are less prone to avalanches than open spaces. If you come across a chute-shaped clear area of a slope where trees are suspiciously absent, that could be a path of frequent avalanches.
Most (not all) avalanches occur on slopes between 30 and 45 degrees, and most (not all) avalanches occur on slopes facing north, east, and northeast. Bowls and gullies are danger areas where a lot of the snow from an avalanche could end up. If you have to cross a suspect slope, do it slowly and cautiously, as otherwise you might set off an avalanche yourself. If you have to cross a bowl or gully, do it quickly.
Avalanches occur most often during or in the first 24 hours after a snowstorm. The heavier the snowfall, the greater the danger.
Avalanches occur more often on the leeward side of a mountain than the windward side. (The windward side is the side wind mostly blows up, and the leeward side is the side wind mostly blows down.)
Avalanches occur most often after sustained below freezing—especially below zero Fahrenheit—temperatures, or after sustained warmer temperatures above freezing. When the temperature goes back and forth above freezing when the sun is out and then below freezing again during the night, the melting and refreezing of the snow can actually add stability.
Visible or audible signs of a weakened snowpack that could be prone to avalanches include cracks across the surface of the snow, small slabs of snow shearing off, and hollow or “whumping” sounds as you walk or snow over the ski.
Another important element of preparation is to obtain and carry with you the proper equipment just in case you do encounter an avalanche.
You should have with you a lightweight, portable, plastic or aluminum shovel, collapsible probes or ski pole probes, and an avalanche beacon set to “transmit.” If you’ll be in especially risky areas, an “avalung” is a snorkel-like device that will allow you to breathe for up to an hour underneath snow, and for about $1,000 an “avalanche airbag” is something you can inflate with a parachute-like string that will make it highly likely you’ll remain on the surface of the snow during an avalanche.
In case you are stranded for an extended period, you should also have water, food, a first aid kit, a butane lighter or waterproof matches, candles, some kindling, and a survival blanket. Your backpack should be such that you can maneuver fairly easily in it, and remove it quickly.
If you do indeed find yourself in the path of an avalanche, you’re not going to be able to outrun or outski it (the wall of snow will be traveling at speeds up to 80 MPH). Your goal instead is to stay on top of it if at all possible. If you can orient yourself, lie flat on your belly facing downhill, and in effect try to body surf your way down. If you can steer at all with your hands, you may be able to avoid obstacles in your path.
* What to Do If You Are Buried By an Avalanche
If in spite of your best efforts you are buried by an avalanche, there are things you can do to give yourself the best chance to survive an extremely dangerous situation.
You’ll likely have very little mobility, little ability to dig toward the surface and free yourself. So unless you’re practically at the surface already, you’re only hope is for someone to rescue you. That’s why hopefully you’ll have your avalanche beacon transmitting, as otherwise locating you will be like finding a needle in a haystack.
Once the snow settles after an avalanche, it hardens surprisingly quickly. Your first priority is to give yourself space to breathe, as most avalanche deaths are from suffocation. You may have only a few seconds to work with, Take a deep breath and hold it to expand your chest; don’t let the snow encase you and harden when your chest is not expanded. Use your arms and hands to punch at the snow immediately in front of your face to try to hollow out an air space.
Unless you can hear rescuers above you, don’t scream, as this only uses air and won’t be heard anyway. Try to remain calm and breathe in a steady, controlled manner.
If you are not close enough to the surface to dig out, yet you are close enough to maybe reach a limb in that direction so it pokes above the surface, stick your foot or hand out so it will be visible. (One trick to figure out what direction is up is to use gravity by spitting into the open space in front of your face. Wherever the spittle goes, that’s down.)
If it’s not you that’s buried but a companion, set your avalanche beacon to “receive.” Look for visible signs of where the victim might be buried. Use your probe or ski poles to poke down beneath the surface of the snow. When you locate the victim, use your snow shovel to dig them out. Remember that every minute, and even second, counts. A person will not survive for long under there.
* What to Do If You Are Stranded By an Avalanche
If you are fortunate enough to avoid being buried when an avalanche strikes, you could still be at risk if you are stranded by it.
If you are stuck for the night, your best option is to construct a snow cave for shelter.
If possible, dig the cave into a small slope or snowbank that is at least six feet deep. Dig an entryway tunnel about three feet long, then angle upward and expand into a larger area. This interior of the cave should be a little higher than the entryway, so it traps warmer air. There needs to be at least one foot, preferably at least two feet, of thickness of the cave ceiling so it doesn’t collapse. Smooth the walls and ceiling so melting snow runs down the sides instead of dripping from the ceiling.
Punch a ventilation hole through the ceiling with a probe or ski pole. Close off the entryway.
Wrap yourself up in your emergency blanket. You can light a candle for heat.
Sources:
“Avalanche Awareness.” National Snow and Ice Data Center.
“Avalanche Safety.” Outdoor Places.
“Learn How To…” Forest Service National Avalanche Center Avalanche Awareness Website.