Turnagain Pass

And the avalanches keep coming… After two weeks of wet, windy and rainy weather, the snowpack below 3,000′ continues to saturate into mush and slide off the mountains; in some cases taking the season’s snowpack with it. If you didn’t know it was still March, you’d think it was late April out there. Another batch of fresh wet slab avalanches were seen yesterday at Turnagain Pass and in Girdwood. These were on Sunburst, Magnum, Cornbiscuit and Seattle Ridge as well as Orca and Maxes in Girdwood. With rain falling as high as 3,000′, we are seeing wet slabs break anywhere between 2,000′ and 3,500′. We are undergoing an impressive avalanche cycle and if you’re itching to get outside, come down to the motorized lot today at Turnagain for our meet and greet and watch the avalanche extravaganza from a safe distance!

To put things in perspective quickly, over the past two weeks there has been upwards of 16″ of rain in the Girdwood Valley and 10″ at Turnagain Pass. As we know, the snow line has fluctuated from 1,000′ to 3,000′ during this time, yet is getting warmer and warming with each storm. This morning temperatures are some of the highest we have seen with 4,000′ peaks bumping up to 30F. This is quite a shock to the snowpack. Remember, wet slab avalanches are unpredictable and unsurvivable if someone was to get caught. The message remains – stay well away from any avalanche terrain including runout zones! There is a change is on the horizon however, clearing skies are expected Monday and Tuesday. What the sun and heat will do to the snowpack will be the next question. 
 

Large wet slab on North facing Sunburst, seen from the Center Ridge parking lot. Released overnight on 3/21 or yesterday morning 3/22. This slab released very near the ground – a closer up image can be found HERE.

West face of Magnum released again sometime late Thursday night, 3/21. The crown is barely visible and debris ran over old debris from last week. 

Wet slab on the lower North aspect of Cornbiscuit. Released overnight on 3/21. Another example of how unpredictable the mountains are during this wet weather. 

Crown on Orca Mtn, at the head of Girdwood Valley, runs full width. Released overnight on 3/21. Debirs ran full path and into the trees. Image taken from the Tesoro. 

Storm Slabs:
What about the upper elevations? Yes, it has been snowing at the higher elevations, yet one must brave the gauntlet of the mid elevations to get there and then hope there is enough visibility to navigate the terrain safely. Although we have little high elevation data since the onset of this two week storm series, we know roughly 1-2′ of new snow has fallen over the past 24-hours with strong easterly winds and therefore can expect the classic storm snow avalanche problems (wind slabs, sluffs and storm slabs) along with cornice falls. Furthermore, Turnagain is looking at 10+ feet of settled storm snow since March 8th and avalanches breaking this deep (on the early March high-pressure surface) are possible – which is a very large avalanche. 

South of Turnagain in the Summit Lake and areas in the interior Kenai Peninsula have a very thin snowpack compared to Turnagain. A variety of old weak layers (facets and buried surface hoar) sit in the mid and base of the pack, which have been reactivated by the current warm temperatures and rain. Over the past few days numerous large wet slab and dry slab avalanches have released. These types of avalanches remain possible until a solid re-freeze occurs.