Snowfall amounts over the past 24 hours ranging from 6” in the lower elevations to 18” in the higher elevations are bringing with it all of the issues related to storm snow.
Loose Snow avalanches
Yesterday my partner and I were able to easily produce sluffing in steep terrain, generally over 40 degrees. Loose snow sluffs will be easy to trigger today and could entrain enough snow to knock people off of their feet. This issue becomes exacerbated when traveling above terrain traps such as cliffs, trees, and gullies.
Enough snow has fallen over the past 24 hours to create slabs without the presence of wind. While the general set up on the surface is loose snow, slabs were beginning to form in sheltered areas late in the day yesterday. Be on the lookout for shooting cracks when traveling on terrain 35 degrees and above today. While these slabs are generally soft, the potential exists for them to propagate across slopes and run far.
Winds out of the East cranked up enough yesterday afternoon and into the night to create wind slabs up to 2 feet in depth that will be very sensitive to the weight of a person today. Avoiding leeward slopes above 35 degrees is your best bet for avoiding this problem. These newly formed slabs also have the potential to trigger deeper layers in the snowpack.
The most prominent weak layer above 3,500’ is facets sitting on the stout January crust. This layer (along with the crust) has been associated with remotely triggered avalanches over the last week. Since Feb 7th, up to 30” of snow with 2” of water has fallen in the higher elevations. This slab has had time to settle and become more dense. The interface between this slab and the January crust is suspect. Visibility yesterday limited our ability to assess this interface. Because of this lack of information, this layer & the slab above it are guilty until proven innocent. Avoidance of steep (over 35 degree) upper elevation starting zones and cross loaded gullies will be the best management tactic related to this problem today.
Winter Part 2 has arrived!
In the past 24 hours the Turnagain Pass SNOTEL site has picked up 14 € of new snow with 1 € of water. The Girdwood Valley has seen less amounts, with stations averaging 6-8 € snow with .5 € of water. Winds that picked up overnight have calmed this morning. Sunburst averaged 20mph with gust to 69mph. Ridge top temps have averaged in the low teens and are currently reading in the high single digits F.
Today expect a continuation of light snowfall. Accumulations of 2-4 € are possible. Temperatures at 1,000′ will be in the teens to low 20s F. Winds will be out of the East at 10-15 mph.
A very large area of Low pressure centered over Kodiak island will remain in place through the weekend. Expect light snow with occasional breaks in the clouds to continue through the next several days.
|04/10/21||Turnagain||Observation: north sides||lance breeding|
|04/09/21||Turnagain||Observation: Girdwood to Turnagain Road Observations||W Wagner Forecaster|
|04/05/21||Turnagain||Avalanche: Resort bowl Seattle creek head wall||Clint Kyffin|
|04/04/21||Turnagain||Observation: Center Ridge||Andy Moderow|
|04/03/21||Turnagain||Observation: Repeat Offender – Seattle Ridge||Troy Tempel|
|04/02/21||Turnagain||Observation: Seattle Ridge||Wagner / Schauer Forecaster|
|04/01/21||Turnagain||Observation: Pete’s||Schauer/ Cullen Forecaster|
|03/31/21||Turnagain||Observation: Tincan||Schauer/ Rothman Forecaster|
|03/30/21||Turnagain||Observation: Eddies||Johnston-Bloom / Kinney Forecaster|
|03/30/21||Turnagain||Observation: Sunburst North||lance breeding|
Status of riding areas across the Chugach NF is managed by the Glacier and Seward Ranger Districts, not avalanche center staff. Riding area information is posted as a public service to our users and updated based on snow depth and snow density to prevent resource damage at trailhead locations. Riding area questions contact: firstname.lastname@example.org
|Area||Status||Weather & Riding Conditions|
This is a general backcountry avalanche advisory issued for Turnagain Arm with Turnagain Pass as the core advisory area. This advisory does not apply to highways, railroads or operating ski areas.