Turnagain Pass

There were no new avalanches reported yesterday. With cloudy skies and poor visibility it’s tough to get a good look at what is happening on the slopes during this warm stormy weather. Even those debris piles seen from the road can look fresh if they get some rain on them. Hence, there is uncertainty as to what has been happening out in the backcountry in general for the past couple days. The last known avalanches were two glide releases in the Summit Lake area on Friday, and one small glide avalanche on south facing Eddie’s Ridge on Thursday.

The warm, wet, and windy weather is over Girdwood, Portage, Turnagain Pass, and the Kenai Peninsula for what looks to be another couple days. Yesterday, Portage Valley saw just over an inch of rain but only a few tenths was seen elsewhere. The rain/snow line has been hovering around 1,500′ in general. More, and possibly heavier, precipitation is expected today. The rain/snow line should be between 1,000 and 1,500′. Up to 4″ of new snow could be seen above 1,500′ in most areas with closer to a foot at the higher elevations in Portage, Placer, and Seward.

Wind Slabs and Cornices – Above 2,000′:  The ridgetop winds have been strong from the east for almost 2 days now; averaging in the 20s mph and gusting in the 50s at times. We can assume wind slabs are forming with the few inches of new snow that is falling. How much of the older crusty snow the winds are able to pick up and move into wind slabs is a question; probably not a whole lot. If you do head out today into the higher elevations, watch for wind slabs near ridgelines, steep gullies, and convex rolls. As always, pay close attention to red flags like shooting cracks or collapsing in the snowpack along with looking for stiff snow over softer snow.

Wet Avalanches – Below 2,000′:  At elevations below 2,000′ we think there has been some degree of wet snow avalanching occurring, nothing very big that we know of yet. With continued rain today, more natural wet snow avalanches are possible. If you end up on a slope with wet saturated snow, be mindful you could trigger a wet snow avalanche. These can be large and dangerous if they are on big steep slopes where they can gain momentum and entrain more wet snow as they move down hill.

South facing slopes of Peak 4940. This is looking north from just west of the Johnson Pass trailhead. Many wet snow avalanches have been filling in the gullies over the past week. Thanks to Joel Curtis for the picture, 3.24.2024.

Turnagain Pass yesterday afternoon. A bit soggy but the sun should come out later this week! Photo from the RWIS webcam that is now back online, 3.24.2024.

Precipitation for today (Monday) into tomorrow. Seward area as well as Portage is clearly the expected winner, yet rain line in these areas should be higher, closer to 2,000′ compared to 1,500′ inland. Thanks to the NWS for the graphics found HERE.

We are still concerned with a weak layer of facets and surface hoar that was buried two weeks ago. The warm stormy weather and our event on Saturday has kept us out of the mountains for a couple days, yet we still think there is a chance a person could trigger a 2-3 foot deep slab. These persistent weak layers are tricky to assess, since they can sometimes cause avalanches even when you don’t see any of the classic warning signs like cracking or collapsing. Unfortunately, from what we have been seeing, it seems like this weak interface is most concerning right in the middle of our advisory area on Turnagain Pass. Keeping this layer in mind we be prudent. As always, be sure you are only exposing one person at a time to avalanche terrain and watch your partners from safe areas outside of avalanche runout zones.