Turnagain Pass

There were no known avalanches triggered yesterday. The last known avalanches were two days ago during and right after Sunday/Monday’s storm (10-18″ of storm total). These were small human triggered avalanches in the new storm snow and some larger natural avalanches in the higher terrain. Photo below of one these larger natural slides on Seattle Ridge.

Natural wind slab avalanche on the front side (SE face) of Seattle Ridge. Avalanche looked to have released on Monday, 2.6.23, at the tail end of the storm. Photo taken 2.7.23.

Cloudy skies, a few snow flurries, and light variable winds are on tap for today. This should not be enough weather to impact avalanche conditions. Hence, the main avalanche concerns will be how the storm snow from Sunday and Monday is bonding to the old surfaces. Anywhere from 10-18″ of snow fell during that storm. I was out on Seattle Ridge yesterday hunting for areas the snow had not bonded well. I had no luck. This is great news for improving stability, but also only one data point. Things to watch for today:

• Wind slabs in the higher elevations. Strong winds during the storm clearly built wind slabs and whether these are still touchy or not is the question. Watch for cracking in the snow and feel for stiffer snow over softer snow. Wind slabs could be quite stubborn, which can allow us onto them before releasing.
• Storm slabs on steep slopes sheltered from the winds. Keep an eye out for any signs the new snow isn’t bonding. Quick hand pits, jumping on small test rolls/slopes, and watching for any signs the snow is cracking around you are good ways to assess this.
• Cornices are big. As always give these guys a wide berth.

Even though things are looking better for stability, remember to always follow safe travel protocol. This is exposing one person at a time, having escape routes planned, and being sure our partners are watching us and know how to use their rescue gear in the event an avalanche releases. Also, don’t forget there is a layer of old buried surface hoar under our feet – mentioned below in Problem 2.

One of many quick hand pits on the backside of Seattle yesterday. This one is in Main Bowl around 2,200′. No weakness was found between the storm snow and the old surface. 2.7.23.

Buried 2-4′ deep now is that Jan 10th buried surface hoar that created a rash of human triggered avalanches over two weeks ago. This layer has been showing signs of healing in general, but not completely. John had concerning snowpit results on Pete’s North on Monday. If you missed it – check out his video HERE.

This layer likely became more reactive with the new load of snow. With quiet weather ahead, the layer should become less reactive again. How likely it is we could trigger it is the big question. It could be fairly unlikely at this point, but there is still a lot of uncertainty. For now, don’t forget that layer is there and that it could create a very large avalanche, especially in steep and consequential terrain.

We are still tracking the Thanksgiving facet/crust combo at the base of the snowpack. In the Turnagain Pass area where the snowpack is thick we believe this layer to be un-reactive and now in a dormant phase. However, in shallower snowpack zones, such as Silvertip and south of the Pass proper, there is still some uncertainty. If the layer is still an issue, it would be in these shallow zones. Other questionable layers may also exist in shallow areas. It’s good to keep this in mind if headed to areas where the pack is less than 6′ feet deep or so. A surprise, or outlier avalanche, may not be out of the question.