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Trail report: Avalanches in mountain country

You may think that avalanches only kill skiers — “They won’t kill me since I don’t ski.”

That is not always the case since living in mountain country provides more dangers than many of us are likely to know. With snow down to our yards (and my dock) it’s time to talk a bit about what lingers above us. 

Many of us love to hike, run and ski on Mt. Marathon, Lowell Canyon and Mt Alice. Although the evidence of it is covered up now, it was apparent on Saturday and Sunday that, even with little snow coverage, Marathon’s Jeep Trail is an avalanche terrain trap. With a deeper snowpack and previous poor weather conditions (i.e. rain on snow, melt/refreeze, high winds) we are set up for what could be a dangerous avalanche cycle should you find yourself in avalanche terrain.

What causes an avalanche?

Well it is a number of factors combined but to keep it simple: snow, a steep enough slope and a trigger. 

My favorite form of precipitation, snow, takes many forms snow. It can be anywhere from dry, sugary snow to heavy, wet cement like we tend to see here. Temperature, wind, humidity all affect the snow quality and how well snow bonds to the slope and older snow. Snow qualities and depths can be very different from mountain to mountain and even slope to slope.
Generally, snow does not slide on flat ground but it does not need all that steep an angle to cause snow to move. Most avalanche forecasters use the numbers 30-45 as slope angles to avoid during avalanche conditions. This does not mean snow can’t slide below 30degrees and it is only expected that slopes over 45 are too steep to retain enough snow to avalanche, which is not always the case. 

Like a gun, avalanches need a trigger as well. These may be natural causes; rain, wind, too much snow, and as we’ve felt lately; earthquakes. The scariest triggers of all however are our friends, family and pets. 
Be it a skier dropping into a fresh powder line, a snowmachiner highmarking a steep couloir, a dog chasing a bunny across a slope or a hiker on the Jeep trail, they may all trigger an avalanche enough to bury themselves or others.  Now you’re probably asking “How if I’m on the Jeep trail on the bench of Marathon can I trigger an avalanche?” Without going into too much detail, certain conditions set up the ability to remotely trigger an avalanche.

My hope for bringing this topic isn’t to scare you off of your favorite trails this winter but merely to help you make the safe decision while traveling in the mountains. Things to look for before venturing into the mountains: past weather (has it recently snowed, have temps changed rapidly, has it been extremely windy, do I see other recent avalanches), avalanche forecast (we don’t currently have one for our area but a valuable resource is CNFAIC.org), and a buddy. 

Be safe and Let it snow!