Turnagain Pass

The high-pressure over Southcentral Alaska will continue for at least another couple days. With mostly clear skies and light winds, our main concerns for backcountry travel will relate to ‘Normal Caution’ issues. This includes wet loose avalanches late in the day, cornice falls, small slabs, and glide avalanches.

Wet loose avalanches:  The springtime freeze-thaw cycle will continue like clockwork the next couple days. The snow surface is able to re-freeze overnight, due to clear skies, then heat up considerably during the day. The middle of the day (solar noon) is around 2pm right now. The hottest part of the day is a couple hours after that, between 3-5pm. Paying close attention to how sloppy and wet the snow surface gets late in the day is key. Once our boots punch though wet snow to the boot-tops it is time to head to a cooler aspect. Wet loose avalanches can start small and grow quite large on steep sustained slopes.

Cornices:  Although we have not heard of a cornice fall in the past several days, we have to assume they are getting weaker and closer to failure each spring day. It is worth it to us, and anyone under us, to give these monsters a very wide berth. They can be very dangerous and life threatening.

If you are headed to the upper elevation dry and shaded aspects, remember there was some wind last Friday. Shallow lingering wind slabs could still be littered about. Always keep an eye out for hollow feeling snow, cracking in the snow around you, and any signs of wind loading. In addition, keeping strict on safe travel protocol is a good habit during ‘green light’ conditions as well as red light. The main things are exposing only one person at a time, having escape routes planned, and watching your partners closely.

Extremely large cornices overhang the Byron Glacier Valley. If one of these is to fall, it will run over the famous ‘ice caves’ that are essentially formed by avalanche debris that does not completely melt during the summer. It is prudent to avoid this area until the snow has already avalanched. Photo taken Sunday, 4.17.22. 

Glide avalanches are occurring daily from Girdwood to Seward. They are easy to see because they leave a dark stain on the track of the avalanche and have some dirt entrained in the debris. They are often, but not always, preceded by a crack. The crack is usually dark and easy to see, giving us clues that a glide avalanche could happen at some point. They are not triggered by people, rather occur unpredictably. All in all, staying out from under glide cracks and avoiding areas other glides have occurred is a good bet. Avoiding the bottom of Seattle Ridge is a great example as many glide avalanches are occurring on the road side (photo below).

Glide avalanche that pulled out a ‘slab’ of snow on the way down. This is on the road side of Seattle Ridge and occurred Sunday. Photo by Andy Moderow, 4.17.22.

Glide release seen on the new Sunburst webcam.

Forecaster John Sykes and Intern Allen Dahl installed the camera provided by the Friends group last week. Thanks everyone – awesome seeing the sunrise on Peak 4940!