Soldier & Wood River Valley Mtns

You could trigger a large avalanche on shady slopes (NW-N-NE-E facing) at mid and upper elevations. In these areas, slides can be triggered remotely—from flatter terrain below, above, and to the sides of steep slopes. Wind drifts that formed will be small, but may be sensitive to your weight and can knock you off your feet. Safer conditions exist in south-facing terrain at low and middle elevations.

HEADING INTO THE STORMWhile a good portion of the rest of the country languishes in record-setting temperatures, we find ourselves barreling towards a very white Christmas. The first in a long series of storms moves into our area late tonight. This round will be a prelude to what is to come, just a few inches to help freshen up the skiing and riding conditions. So why am I writing about this today? I'd like to get you to think about the snowpack conditions that you are experiencing in the mountains not just as a moment in time, but as being connected to the past and future. The snowpack that sits on the ground is a record of the season's weather, written in snow and ice. This record is written by the day.

When you head out into the backcountry today the snow surface that you are traveling on will be what tonight's storm falls on. Today is your last chance to easily look at this before it gets buried. It is much simpler to look crusts, facets, and surface hoar when they are still on the surface. We name weak layers by the date that they are buried, it helps us to keep track of them across our region and to communicate this information to others. The weak snow from October storms was buried on December 11th, so we call it 12/11. On Sunday, a quick-hitting storm buried another snow surface. This one varies in character across the region, but includes crusts, facets, and the combination of the two. This is 12/19. When the snowfall starts late tonight or early tomorrow we will have another player in the game. As you head to your favorite backcountry location today spend some time looking at this surface. Are you finding crusts? What about those pesky, sugary grains known as facets? Maybe you are seeing some surface hoar flakes that formed last night or the night before? Even though snow can be infinitely complex it is available to all of us. We don't need an expensive gadget to look at it, we can pick it up and interact with it with our hands, eyes, and tongue. 

As each additional layer gets buried the snowpack picture becomes more complicated. Fortunately, many of these layers don't end up creating long-standing problems and we can forget about them, freeing up mental space to focus on the ones that are causing problems. It will be some time before we are forgetting about 12/11, weeks and weeks at a minimum. The upcoming storm will be testing all of these layers. In times when the behavior and distribution of these layers is uncertain (right now), the amount of terrain that is safely available to us is much more limited. In addition, our focus needs to be split in multiple directions: we are paying close attention to whether or not the slope we are on has old snow underneath and we are also thinking about the presence of wind slabs at the surface and what they are resting on. When the backcountry world gets more complex taking a step back and increasing the size of our safety margins is generally a good idea. We had a good little window there where a portion of our terrain was "open" and we were enjoying excellent skiing and riding in terrain that was largely free of avalanche problems. That widow has closed significantly and is about to get slammed completely shut. For the foreseeable future, I'll be heading into the mountains with this in mind.