Introduction

Our Gearheads are passionate about getting out in the backcountry, but we’re even more passionate about clinking glasses together in celebration after the end of a successful day on the snow. What’s a successful day? One where we return home safely. And that includes days where we don’t ski or ride at all because the avalanche report or observed red flags warned us of danger, sending us scurrying home.  

This article is meant to serve as an introduction to avalanche safety. It is not a substitute for on-snow avalanche training. So, take a peek, and then sign up for an avalanche safety class.  

What Is An Avalanche?

An avalanche is the swift movement of snow down a mountain. It occurs when snow becomes too unstable to support its own weight. When friction can no longer hold snow to the mountainside, it succumbs to the downward pull of gravity. 

As snow falls throughout the winter it builds up in layers of varying consistencies. Slab avalanches happen when the bonds between these layers are weak. For example, a snow surface could melt in the sun and then refreeze at night. Then a new layer of snow could be deposited on top of the frozen layer creating an unstable, low friction zone in the snowpack. A loose snow avalanche is the other type, where snow tumbles downhill as a simple result of its huge mass rather than weak layers.  

Avalanches can be triggered by snow pile-up or by human or animal disturbance. 

As avalanches move downhill, they pick up steam, collect more snow, and become bigger. Particularly large avalanches are extremely powerful, weighing as much as a million tons and traveling well over 200 miles per hour.  

Click these links to jump to different sections in the article: 

• How Avalanches Occur 
• How Read An Avalanche Forecast 
• Red Flags To Watch Out For 
• Education Resources For Avalanche Safety 
• Avalanche Safety Gear List 

How And Where Do Avalanches Occur?

Slope Angle:

Avalanches are possible on any slope steeper than 30° and occur frequently on slopes between 35° and 50°. Low-angle slopes below steep slopes are also considered to be avalanche terrain.  

Terrain Traps:

Anything that could worsen the consequences of being caught in a slide—for example, trees may increase injury and gullies may deepen burial.

Trigger Points:

These are the most common places to trigger an avalanche, but if conditions are bad enough, a slide can be remotely triggered from flat ground or a ridge. 

Aspect:

The slope’s relation to the sun and wind may dictate the presence of avalanche danger. In North America, NW-N-NE (shaded) aspects typically have more slab avalanches and south facing (shaded) solar aspects are more likely to have wet/loose avalanches.

Persistent weak layers:

Weak layers deep in the snowpack can trigger a slide weeks after a storm, even when no other red flags are present. Identify weak layers by listening to your local avalanche report or by digging a snow pit and identifying them for yourself. Take a class to learn how to dig a snow pit. 

Avalanche Safety Protocols:

• Never expose more than one person to danger at a time. 
• Stay spread out if you must move together. Watch each other from safe locations and avoid stopping on or below avalanche terrain. Never ski directly above a partner or another group. 
• Stay alert to changes in aspect, elevation, or weather that may alter snow stability. 
• Avalanche conditions change throughout the day. Your initial assessment of the danger may not be accurate after you travel even a short distance. 
• Avoid groupthink and keep all options open. 
• Many accidents happen as a result of experienced backcountry travelers not sharing concerns with each other. Always voice your concerns, even if your partners are more experienced, and ask others in your group if they have any concerns. Address all concerns and make a group decision on how to proceed. 
• Always be prepared to execute a rescue. 
• Stay up to date on your rescue practice, and have your beacon, shovel, and probe readily available at all times. Don’t bury any of this gear in the bottom of your pack. 
• Do everything you can to not get caught in a slide. 
• Always have an exit plan in case an avalanche begins. If caught, do everything you can to avoid being buried. Remember, if buried, your chance of survival is only 30%. 
• If your partner gets caught, do not leave the scene to find help! 
• You have only 15 minutes for a good chance to recover someone alive. Watch your partner as long as you can to establish a last-seen point where you can begin your search and yell to alert others of this location. Quickly establish a leader and make a plan, then get to work conducting your search.  
• Reminder! This article does not tell you how to do a search and rescue. In order to gain those skills, seek avalanche training

 

How To Read An Avalanche Forecast 

Avalanche centers have agreed upon a consistent way of measuring avalanche severity. The five tiers of the Avalanche Danger Scale are Low, Moderate, Considerable, High, and Extreme.  

 

It’s important to note that danger does not increase in a steady linear manner as the tiers go up, but rather on a curve. This means that risk increases about two-fold at each tier. For example, when danger is Extreme, you’re taking on about ten times as much risk as you would at the Low tier.  

Many avalanche centers use what’s called the Danger Rose. [image here if possible] It’s essentially a bird’s eye representation of a mountain labeled with elevations and aspects, so it looks a little like a three-dimensional eight-point compass. Avalanche centers update the rose daily with colors that correspond to the Avalanche Danger Scale. This way skiers and riders can choose aspects and elevations with lower avalanche risk. 

Current Avalanche Conditions in the Salt Lake City mountains (courtesy of the Utah Avalanche Center)

 

Red Flags To Watch Out For

Along with reading the daily avalanche report, you should always stay alert when you set foot on the snow. Keep your eyes and ears open for clues signifying increased avalanche danger. If you notice any of these, take them seriously and let them influence your judgment. Avoid or leave avalanche terrain when red flags are present.  

Here are five avalanche warning signs to watch out for: 

1. Significant warming:

Warming temperatures can cause snow creep and wet-slide avalanches. Wet slides can occur without a human trigger. Melting can also affect the overall stability of the snowpack. One clue to warming snow is the presence of roller balls on the snow surface.  

2. Wind loading:

Windblown snow can overload leeward slopes even when it’s not snowing. Take notice of snow surface patterns indicating wind direction and snow transportation and deposition. After identifying prevailing wind directions, look out for cornices: overhanging masses of snow on the leeward sides of mountain crests that can easily break free and slide. Wind slabs can look smooth and rounded. These pillowy-looking areas may also feel firmer under-ski than nearby areas.  

3. Recent avalanches:

If you see evidence of recent avalanches or if your local forecasters have reported them then more are likely. If you can’t tell how recent an avalanche was, assume it just happened. Find more information at avalanche.org.  

4. Signs of unstable snow:

Look for cracking or collapsing snow and listen for hollow “whumpfing” sounds. Cracks often indicate that an area of snow has collapsed. “Whumpfing is the sound of this occurring—air rushing out from lower layers of snow.   

5. Heavy snowfall or rain:

Avalanches are often triggered the day after a storm due to significant loading. Sunny does not mean safe.

 

Education Resources For Avalanche Safety

Take an AIARE (American Institute for Avalanche Research and Education) or AAI (American Avalanche Institute) Level 1, 2, or 3 multi-day course starting with the basics and providing professional-level theory and practice. Available all over the western U.S., this is where most avalanche pros begin their study. Class schedules are listed here. 

For a map with state-by-state listings, you can also check the Avalanche.org website. 

This video covers basic avalanche awareness, but it is not a substitute for an avalanche course. It is not meant to replace on-snow education, it is meant to be a refresher for those who’ve taken these classes or as an introduction for new backcountry skiers and snowboarders. 

 

Avalanche Safety Gear List 

Most of us are familiar with the main three tools carried in the backcountry: beacon (transceiver), probe, and shovel. But it’s important to consider other basic safety when you’re outdoors, particularly in the mountains during winter conditions. A first aid kit, a map & compass, a headlamp, and proper warm layers are all crucial safety items. Bring your puffy, yes, but also maybe even an extra pair of gloves, extra buffs, and an emergency bivy and a firestarter kit. In the event of a worst-case-scenario, you need to be ready.  

Communication in the backcountry is key, particularly for riding one at a time down a line. Consider bringing a 2-way radio for speaking to your partner throughout a tour. This is especially important when trees or terrain may block line of sight. 

Remember that gear mishaps can happen. If you need to fix a binding or boot buckle, a multi-tool, duct tape, and a utility strap are great to have on-hand.  

Take snow science tools into the backcountry with you: an inclinometer for measuring slope angle, a snow saw for cutting out blocks of snow to examine, and a snow kit for analyzing the snowpack on the slope you’re looking to ride. 

Have more questions about avalanche safety? Connect with a Gearhead: Call 1-800-409-4502 or chat with us online 24/7. 

Avalanche Safety Gear List 

• Beacon: Mammut Barryvox S Beacon 
• Shovel: Backcountry Access Dozer 1T Shovel 
• Probe: Backcountry Access Stealth 270 Probe 
• Airbags: Black Diamond Jetforce Split 25 Backpack 
• Helmet: POC Obex BC MIPS Helmet 
• Map & Compass: Compasses 
• Warm Clothes: Backcountry GORE-TEX Kits 
• First Aid Kit: First Aid Kits 
• Bivy: S.O.L Escape Bivvy 
• Headlamp: Headlamps 
• Repair Kit: Ski tools and repair kits 

The Last Word On Avalanches (For Now) 

We love skiing and riding in the backcountry, but we love returning home safely even more. If you take one thing away from this article, it should be this: There is no substitute for on-snow avalanche training. This article is meant to serve as an introduction, so you know what next steps you need to take to be safe on the snow. Here’s our last word on avalanches (for now): 

• Take a class 
• Learn how to read avalanche forecasts 
• Get proper equipment 
• Practice, practice, practice avalanche safety on the snow (outside of avalanche terrain) 
• Make safe decisions while touring 
• If there are red flags present, don’t go! 
• Safely return home from fun touring days 

Informative Links

Book a Course: https://avtraining.org/upcoming-public-avalanche-training-courses/ 

Check the Forecast: https://utahavalanchecenter.org/forecast/salt-lake 

Educate Yourself: https://www.youtube.com/playlist?list=PL3iULOH9egqe7zNZo3Mg7XX_nU3IrMrqO 

UAC Education Hub: https://utahavalanchecenter.org/education/other-classes

All Avalanche Safety Gear: https://www.backcountry.com/avalanche-safety 

Follow the UAC on Instagram: @utavy 

Listen to the UAC’s Podcast: https://www.stitcher.com/show/utah-avalanche-center-podcast 

Listen to The Avalanche Hour Podcast: https://www.stitcher.com/show/the-avalanche-hour 

 

FAQ

How do you stay safe in avalanche terrain? 

Get the gear, get the education, and check the forecast.  

What happens if an avalanche hits you?

While the best strategy is to avoid avalanche terrain, if you find yourself in an avalanche the best thing to do is be equipped with an avalanche airbag and deploy it. This can help you float to the top of the debris, and protect your vitals from impacts against rocks and trees.  

What should you do in an avalanche?

While it’s very hard to maintain your awareness if you’re caught in an avalanche, there are a few things you can do. First and foremost, try to maintain an airway and keep your head above the snow. If full burial is unavoidable, create an air pocket by bracing your hands and arms around your face. If it’s impossible to maintain an airway but you’re still close to the snow surface, it can be useful to try and stick an arm, leg, or ski pole above the snow surface for your partners to spot you more easily.