Winter Returns: Skiing Considerable Danger

This weekend heralded a true return of snow to the Pacific Northwest, and with a less-typical SW flow, the Mt Hood area received more snow than the more-Northerly cascades. With an avalanche class lined up for Sunday, but a clear schedule on Saturday, I was eager to sneak out and see if we could nibble some powder. Taylor, my usual compadre, was also free, and we found room in our car for Angie, my longtime friend and recent splitboard convert.

The avalanche forecast called for considerable hazard (human triggered avalanches likely), with storm slab on all aspects and wind slab on lee aspects offering the primary concerns. Our plan was access treeline by a densely treed ridgeline, and to take a look at the East and West aspects of the ridge. We joked in the parking lot that the snow looked good but might end up being too scary to ski.

The skintrack was a beautiful change from this season’s usually spare snow, climbing through ghostly trees piled high with the fresh snow. The snow was ongoing, stacking up at about 0.5″/hour throughout the morning. Surprisingly, the forecast 20 mph winds didn’t materialize, and the snow fell straight down out of the sky. Optimism crept in.

Multiple parties had broken trail to treeline, and when we arrived at the usual spot, there was a small amount of cornicing to the East, the more likely aspect for good skiing.

Kicking at the cornice as we made out way along the ridge, it was easy to trigger 5-10″ wind slabs that slid away from the ridge before breaking apart and stopping in the deeper snow below. The hazard was predictable and manageable, and with eyes on I was able to make a ski cut and dig a quick pit to confirm our suspicions: the wind slab was isolated to just below ridge line, and below the slab lay several hundred feet of unconsolidated fresh snow well-bonded to the base.

That’s the recipe for a powder day.

We skied two amazing laps of light snow flying around our waists, conservatively leapfrogging and staying within sight of one-another. Nothing moved, cracked, or sluffed. The conditions were different from those predicted by the avalanche center and we were rewarded for poking around.

With two laps under out belt, and a tired partner ready to hit the bar, we decided to poke onto the opposite aspect, which could offer a shorter exit to the car. While I’d never skied off this side, Tay said that she had used it several times before with good results.

As I worked my way onto the Western aspect, the first thing that I noticed was a much thinner snowpack, tagging rocks willy nilly as I skinned a diagonal onto the sparsely treed pitch. The second thing that I noticed was a somewhat slabbier character to the snow. As we collected at an unexposed spot, I dug another quick pit. The snow structure was more layered than to the East, and the storm snow layer indeed was of a slabbier character (4F+ compared to F-). The pit was at once concerning, with isolated blocks collapsing easily on low density snow below the slab, and equivocal, showing no real energy or pop. It was easy to make the slab drop, but it didn’t move. After some discussion, we agreed to conservatively poke our way onto the slope.

I made a bouncing ski cut and a few shallow, rock-mingled turns to a clump of trees, where Tay and Angie joined me. Below, the snow looked deeper and more rolling. We made another leapfrog without incident, and as I skied I felt the snow taking on intermittently stiff and soft character. On our third leapfrog, howevever, fear replaced growing confidence.

Trying to get some of the surface snow to sluff out of curiosity, I made a harder turn near the top of a small roll and then skied down to another tree island. Looking back up, I waived. “Did you hear that?” Tay yelled down. I hadn’t. She yelled back that they’d felt a whumph as I made that hard turn. She told me later that looking 15-20′ upslope of where they were standing, they could see a fracture line where the snow had dropped 2-4″. As I looked up from where I was, I could see a fracture in the new snow across most of the rollers in site, shaken loose by the whumph.

When we cleared the slope to the valley floor, the situation became clear. The slope that we skied had been cross-loaded; the thin and rocky terrain on which we’d started had been stripped by the wind, piling a wind slab onto the area that we’d skied. In a rare moment of feedback, it seems apparent that my pit assessment was true, if only luckily so: the slab was easy to collapse, but didn’t want to move.[divider_line]

Recent news has featured 6 avalanche fatalities in Oregon, Utah, and Colorado. Reflecting on those accidents made me take a harder look at our decision making. I’m not happy that we skied that slope. Human factors were in play.

• Commitment: Though we had inched only 20′ or so onto the slope from the ridge line before digging a pit and making a decision to ski, I had an unquestioned feeling that we were going to ski the slope. With a splitboarder in the group, the idea of transitioning back into a climbing mode to return to the ridge seemed tedious. It was easier to proceed with the plan
• Expert Halo: I help teach avalanche courses, and I’m outspoken. Taylor has an Avy 1 and Angie is naive to avalanche danger. Decision making took part between Taylor and I, and I was digging the pit. I think that we valued my opinion too much.
• Overconfidence: We decided to ski the slope based on a pit that sounds borderline to bad in retrospect. I broke a primary rule and used a field observation to open what should have been a red/closed run based on the avalanche forecast. The slope was in windloaded terrain near treeline, i.e. where human triggered avalanches were deemed likely. Additionally, I thought that we could manage the hazard with leapfrogging on a sparsely treed slope. In retrospect, this was foolishly optimistic. [divider_line]

Coming too close is a blessing in disguise, a learning opportunity not weighed with tragedy. The day stacked up in our favor until overconfidence pushed us onto a slope that we shouldn’t have skied, and we brought a novice friend through that terrain as well. It is certainly something which I will be reflecting on as I make decisions in the future. I usually wonder if I am being too conservative, but now I see how I can easily be pushed to the other extreme by circumstance. The critical point is to keep making decisions rather than riding an unspoken wave. I am convinced that the way to do this is by use of boring and repetitive habits like checklists. Intuitive and creative decision making have no place in the backcountry.

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