Turnagain Pass

The most recent avalanches that we know of were a skier-triggered avalanche on Eddie’s Ridge and two snowmachine-triggered avalanches on the back side of Seattle Ridge Saturday. These look to have failed roughly 2 to 3 feet deep, likely on the January facet layer that we are concerned about.

The crown of this skier-triggered avalanche was roughly 2-3’deep and 80′ wide. Heavy wind loading today will increase the chances of triggering a similar avalanche today. Photo: Rafael Pease, 02.10.2024.

Stormy weather returns today, but unfortunately it’s looking like the wind will be the main event. Easterly winds are expected to quickly increase to 30 to 50 mph with gusts of 40 to 60 mph through tonight. Along with the winds we could see another 1 to 3″ snow in most parts of our advisory area during the day, with the exception of the more coastal areas like Portage, Placer, and Seward, which will likely see more like 3 to 6″ during the day and over a foot of snow by tomorrow morning. Warming temperatures will bring the rain line up to around 1400′ this evening.

That active weather will increase the chances of natural and human-triggered avalanches today. Several hours of winds near 50 mph would have us concerned regardless of the snowpack, and that weak layer that formed back in January is going to make things even worse (more on that in Problem 2). Expect to find dangerous avalanche conditions in the mountains today, and be aware of the potential for overhead hazard as the likelihood of natural avalanches increases through the day. For now, we are still planning on sticking to low-angle terrain and trying to limit time spent in runout zones below steeper avalanche paths.

Cornice Fall: Warmer temps and strong winds will likely make giant cornices over the next couple days. These may fail without notice, and can be a very efficient trigger for a large avalanche. Be aware of this additional hazard, and avoid spending time under them.

The wind was already at work blowing snow yesterday, and it will be picking up today. Photo of Raven Ridge in the Summit Pass area by Heather Thamm, 02.11.2024

As mentioned above, we’re still concerned with the potential for triggering a larger avalanche failing on weak snow buried about 2 to 3 feet deep. This weak layer formed during the three-week dry spell in January, and it is slow to heal. We’ve seen it in all of our snowpits in Girdwood, Placer, Turnagain, Summit, and Seward, and we have found it to be the weakest and most developed between around 1000 to 2000′ elevation. This layer will likely heal with time but another major loading event on the way today will be adding stress and pushing it closer to making avalanches. Keep this dangerous setup in mind if you are trying to find sheltered snow at lower elevations today– the terrain with the best snow on the surface may also be the most likely place to trigger an avalanche on that deeper weak layer. This was likely the culprit for Saturday’s skier-triggered avalanche on Eddie’s Ridge, and we think it will still produce more avalanches before it heals.

It has been a little over two weeks since we last saw a glide avalanche, and we’re starting to think the glide cycle may have gone dormant for now. However, we don’t have any way to predict these massive avalanches so the best practice is still to avoid spending any time under open glide cracks. The series of storms over the past week has made these harder to recognize, which also adds the hazard of falling into a concealed glide crack. Pay careful attention the snow surface, and avoid traveling on or below slopes with exposed cracks or an unusually wrinkled texture.