How to Assess Weather Patterns for Avalanche Conditions

When assessing the avalanche hazard for a large area, weather patterns are one of your best initial clues. Being aware of significant weather events prior to your backcountry travel will greatly increase your knowledge of the snowpack.

Instructions

Difficulty: Moderate

Things You’ll Need:

• Winter Outerwear
• Weather Radios
• Avalanche Beacon
• Avalanche Probe
• Backcountry Snow Shovel
• Backpacks

1. Check a local backcountry store for an avalanche report. This information lists recent weather events and probable hazard ratings. You can also find reports online.
2. Test the depth of new snow out on the trail. A large amount of new snowfall adds stress to the snowpack and increases the chance of a slide.
3. Be aware of any dry cold spells prior to a new snowfall. Extended periods of cold, clear weather can weaken the snowpack, causing new snow to be even more hazardous.
4. Look for signs of heavy wind - cornices, trees blown free of snow, and drifts are all signs that snow has been moved from one place to another. The pockets where wind has deposited snow are less stable than other areas of the terrain.
5. Watch for signs of heavy rain on top of a snowpack. This puts additional stress on the snowpack while eroding the bonds between grains.
6. Feel the air for excessive heat and solar radiation. Warm spring skiing offers some of the safest backcountry conditions. However, when the snowpack becomes too wet, it can cause a loose snow slide.
7. Remember that with any type of weather, a rapid change can cause drastic differences in the snowpack stability.

Tips & Warnings

• The best way to assess weather-related stability is to be aware of it on a continuous basis. An entire winter of weather can affect the stability on any given day in the spring.
• The risks of avalanches are extremely high in many backcountry situations across the country. The eHows on avalanche assessment are designed to increase your awareness and help you make safe decisions. However, a class on the subject or traveling with a guide is recommended for those new to the backcountry experience.