Turnagain Pass Avalanche Forecast

We did not see or hear of any avalanche activity yesterday, however, it seems to have been a very quiet day in the backcountry in general.

The last known avalanche was three days ago. A slab was triggered by Andrew and avy center intern Megan Guinn, just below them when they were digging snow pits on a lower southerly aspect on Tincan. More details HERE.

Although the region did get a bit of weather over the past 24 hours, the main avalanche concern remains triggering a 2′ slab on buried surface hoar. There have been many of these easily triggered for 10 days now, some catching and carrying people last weekend. Slabs have been releasing in open areas in the trees and in the higher elevations. These are being triggered by people on slopes and remotely, next to slopes. It’s starting to get a little trickier because the weak layer is generally buried too deep to rely on hand pits and quick tests we can do easily, without digging in the snow. We are getting to the point where we simply have to remember the problem is there. Even test slopes may not give us great information. That said, sticking to our motto this year, a cautious mindset, conservative terrain choices, and really being aware of our exposure to slopes that have to potential to slide is key.

Early this morning 1-4″ of new snow fell above 1,500′ (rain below…) and winds have been strong enough to move snow around at the higher elevations for 24 hours now. Due to this, we can expect that wind slabs have formed and cornices have grown. These issues are overlying the buried surface hoar problem. If folks venture to the ridgelines today, be mindful of fresh wind slabs and know cornices could be triggered easily and break further back than expected. Any smaller avalanche or cornice fall could trigger a larger avalanche.

As we roll into late January, with 1 hour and 44 minutes more daylight :), the sun is going to become a factor quick when skies decide to clear. This could happen this afternoon, or more likely over the next several days. In this case, we should start seeing avalanches on southerly aspects. Warming by the sun can trigger small loose snow avalanches, but it can also cause larger slabs to release or make them easier for us to trigger. Something to keep in mind moving forward.

Photo of the slab triggered on a southerly aspect of Tincan (2,000′) on Sunday, 1.22.23, by Andrew and Megan. 

It’s getting to be old news, but we are still concerned about an avalanche breaking in buried weak layers at the base of the snowpack, this could create a huge slide. The weak layers are facets surrounding the Thanksgiving crust, buried anywhere from 4-8′ deep now and a foot or two above the ground. Continued small amounts of snowfall, strong winds, and warm temperatures are slowly adding stress to the snowpack.

These kinds of avalanches release during weather events, rapid warming (could we see this on Saturday?), or a person hitting a thin spot in the slab. It’s impossible to say how close certain slopes are to catastrophic failure or not. So in the meantime, our guard remains up.  There is enough to worry about in the top 3 feet of the snowpack, this just puts the icing on the cake this year to keep things more mellow that we may want to.