A busy couple days in the backcountry brought a lot of avalanche activity through Turnagain Pass and Summit. On Thursday a group of skiers triggered at least 5 disconnected avalanches remotely from the ridge (See color picture below). Yesterday, a dog triggered an avalanche on the lower part of Tincan ridge (black and white photo below). Despite the search efforts of at least a dozen people, the dog was not found and is presumed dead. For reference, this is the same slide path that slid almost exactly a year ago.
These avalanches are sliding on older and deeper weak layers. Once they get moving the entire depth of the snowpack can get stripped out. They are unmanageable in size, will trigger remotely, and can connect across large distances.
Terrain management is key to safe travel this weekend. This means stay off steep slopes and avoiding terrain traps and complex terrain.
Black and white photo – lower CFR, Tincan ridge. Crown at 2300 feet elevation
Upper Tincan ridge. Crowns near 3500 feet elevation.
New storm snow will exacerbate the persistent slab problem today as new stress gets added to the snowpack. By late today, the storm snow on its own may be deep enough to be its own distinct problem.
With over a foot of snow expected (possibly 2+ feet), we can expect natural avalanche activity to start late today and continue over night. We will likely reach HIGH avalanche danger during the peak of this storm.
The last major storm was over the Dec 31st/Jan 1st holiday. Since then conditions have been mild and pleasant.
A big change is in the forecast today. A powerful storm is directing a moisture laden southern jet stream from warm lower latitudes straight at southcentral Alaska. The picture below describes the scenario far better than I could in words.
Snowfall is expected to start this morning and increase in intensity this afternoon and into the evening. Wind will be associated with this storm with a ridgetop wind from the East at 56-73mph. Rain at sea level is expected, transitioning to snow at 300-400 feet. Storm totals are predicted in the 16″-29″ range for the next 24 hours.
|04/19/21||Turnagain||Avalanche: Triangle, Seattle creek||Will Morrison|
|04/18/21||Turnagain||Avalanche: Turnagain Pass Road Obs||Andy Moderow|
|04/18/21||Turnagain||Observation: Seattle Ridge, approximately 300 yards south of the up track||Brent Byrne|
|04/17/21||Turnagain||Avalanche: Road obs||Johnston-Bloom / Moderow Forecaster|
|04/16/21||Turnagain||Avalanche: Seattle Ridge||Wendy Wagner Forecaster|
|04/16/21||Turnagain||Avalanche: Turnagain Pass, non-motorized side seen from Seattle Ridge||CNFAIC Staff Forecaster|
|04/16/21||Turnagain||Observation: Sunburst||Lance breeding|
|04/15/21||Turnagain||Observation: Tincan||Schauer/ Rothman Forecaster|
|04/13/21||Turnagain||Observation: Turnagain Pass Road Obs||A Schauer Forecaster|
|04/12/21||Turnagain||Observation: Tincan||Johnston-Bloom / Latosuo Forecaster|
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: email@example.com
|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.