Avalanche Disaster

An avalanche, sometimes called a snowslide, is the rapid flow of snow, ice and/or rock down a slope or mountain. They can be triggered by natural forces such as precipitation, earthquakes or the weakening of snowpack (layers of slow that accumulate in areas of high elevation and cold temperatures).  
An avalanche is a large amount of snow moving quickly down a mountain, typically on slopes of 30 to 45 degrees. When an avalanche stops, the snow becomes solid like concrete and people are unable to dig out. Avalanches strike suddenly and can be deadly. People caught in avalanches can die from suffocation, trauma or hypothermia. Avalanches can be caused by people, new snow and wind, move at speeds of 60 to 80 MPH and peak December through March.

Before you lace up those boots or strap on that board, ask yourself:

  • Do you have the avalanche know-how?
  • Have you checked the latest forecasts at the Sierra Avalanche Center?
  • Is your rescue gear packed and are your skills to use it sharp?
  • Can you spot the five red flags of avalanche conditions?
  • Perhaps it's time to take that avalanche awareness or rescue course?
  • Use proper equipment. This should include helmets and materials to create pockets of air if trapped.
  • Sign up for alerts on current avalanche dangers.
  • Use devices to support rescue.

How to Protect Yourself

Know Your Risk 
Learn about your local avalanche risk. Know the signs of increased danger, including recent avalanches and shooting cracks across slopes. Avoid areas of increased risk, such as slopes steeper than 30 degrees or areas under steep slopes. Get training on how to recognize hazardous conditions and avalanche-prone locations. Sign up for alerts from a U.S. Forest Service Avalanche Center near you. Your community may also have a local warning system.

Preparing Ahead 
Get proper equipment to protect yourself from head injuries and create air pockets. Receive first aid training so you can recognize and treat suffocation, hypothermia, traumatic injury and shock. Wear a helmet to help reduce head injuries and create air pockets. Wear an avalanche beacon to help rescuers locate you. Use an avalanche airbag that may help you from being completely buried. Carry a collapsible avalanche probe and a small shovel to help rescue others.

Warning Signs  
Learn the signs of an avalanche, and how to use safety and rescue equipment.

  • You see an avalanche happen or see evidence of previous slides.
  • Cracks form in the snow around your feet or skis.
  • The ground feels hollow underfoot.
  • You hear a "whumping" sound as you walk, which indicates that the snow is settling and a slab might release.
  • Heavy snowfall or rain in the past 24 hours
  • Significant warming or rapidly increasing temperatures
  • You see surface patterns on the snow made by the force of strong winds. This could indicate that snow has been transported and deposited in dangerous drifts that could release.

How to Stay Safe During

  • Use and carry safety equipment and rescue gear.
  • If your partner or others are buried, call 9-1-1 and then begin to search if it is safe to do so.
  • If you have the proper training, treat others for suffocation, hypothermia, traumatic injury or shock.

Returning After

Know the signs and ways to treat hypothermia.

  • Hypothermia is an unusually low body temperature. A body temperature below 95 degrees is an emergency.
    • Signs: Shivering, exhaustion, confusion, fumbling hands, memory loss, slurred speech and drowsiness.
    • Actions: Go to a warm room or shelter. Warm the center of the body first—chest, neck, head and groin. Keep the person dry and wrapped up in warm blankets, including the head and neck. 
  • Engage virtually with your community through video and phone calls. Know that it’s normal to feel anxious or stressed. Take care of your body and talk to someone if you are feeling upset.