|Signal Word||Size (D scale)||Simple Descriptor|
|Small||1||Unlikely to bury a person|
|Large||2||Can bury a person|
|Very Large||3||Can destroy a house|
|Historic||4 & 5||Can destroy part or all of a village|
Triggering an avalanche on a buried layer of weak snow is the main concern today. The big question is whether or not there is a slab over the weak snow. Slopes that were loaded during the wind event last Thursday (2.11) are most suspect due to the potential for a more substantial slab. Since January 28th we have been talking about a layer of buried surface hoar and near surface facets, and the possibility of triggering an avalanche if you travel on a slope that has a slab over this layer. In addition, there have been subsequent small snow events, a few wind events (from different directions) and more surface hoar and near-surface facet formation. In some terrain there is now more than one layer of weak snow and more than one layer of wind affected snow. During the Thursday wind event there was a natural avalanche cycle with avalanches failing on buried weak snow. There were a couple of small human triggered avalanches reported yesterday and there were a handful on Friday and Saturday. With that data in mind there are a few other things to remember in as you make your travel plan for the day today. Areas with more snow over the January 28th layer like Placer, Skookum and Grandview could have deeper slabs. Additionally, there is a melt-freeze crust buried below weak snow from sea level to somewhere between 1200-2000′ depending on location. This crust facet set-up combined with a slab on top could be a recipe for a larger, more connected avalanche. When you are out today watch for cracks shooting out from your snowmachine or skis, smooth rounded pillows of snow, and ‘punchy’ feeling stiff snow over weaker snow. Steep slopes with wind affected snow should be approached with extra caution. Slabs will mostly likely be found near ridges, on wind-loaded slopes and in cross-loaded gullies. Even shallow slabs can be quite dangerous in high consequence terrain and hard wind slabs may break above you as you travel out onto the slope. Look for signs of signs of instability, choose terrain carefully and use good travel protocol.
Loose Snow Avalanches (Sluffs): In steep terrain that has been sheltered from the wind be aware of your sluff, especially if you are above terrain traps like cliffs, rocks, trees, or gullies.
Cornices: When traveling along ridgelines be sure to give cornices plenty of space, and minimize the amount of time spent traveling below them. Cornices could fail under the weight of a person on skis or a snowmachine, and might trigger an avalanche if the slope below is wind-loaded.
Glide cracks have opened up throughout the area and there was a recent glide avalanche observed yesterday from Girdwood. This type of avalanche is unpredictable, involves the entire season’s snowpack and can be large and destructive. Avoid spending time below glide cracks. If you see any new glide activity, please let us know here.
Yesterday: Skies were overcast becoming broken in the afternoon. Winds were light and easterly and temperatures were in the teens to low 20°Fs at upper elevations and high 20°Fs to low 30°Fs at sea level. Overnight skies were mostly cloudy with temperatures in the teens to low 20°Fs and winds were light and variable.
Today: Skies will be mostly cloudy with a chance of snow showers late in the afternoon. Temperatures will be in the 20°Fs and winds will be light and variable. Overnight skies will be cloudy with light snow, 1-3″ to sea level. Temperatures will be in the low to mid 20°Fs. Winds will be light and easterly.
Tomorrow: Mostly cloudy skies and snow showers in the morning. Light easterly winds and temperatures in the 20°Fs. After a few weeks of not much precipitation, a more potent storm looks to be on track to impact the region Wednesday. However, there is still some uncertainty with temperatures and precipitation amounts. Stay tuned and as always think cold thoughts! #snowtosealevel
PRECIPITATION 24-hour data (6am – 6am)
|Temp Avg (F)||Snow (in)||Water (in)||Snow Depth (in)|
|Center Ridge (1880′)||24||0||0||116|
|Summit Lake (1400′)||21||0||0||42|
|Alyeska Mid (1700′)||23||0||0||109|
RIDGETOP 24-hour data (6am – 6am)
|Temp Avg (F)||Wind Dir||Wind Avg (mph)||Wind Gust (mph)|
|Seattle Ridge (2400′)||19||E||6||18|
|03/06/21||Turnagain||Observation: Eddies/Tincan||A Schauer Forecaster|
|03/05/21||Turnagain||Observation: Seattle Ridge – SE face, road side||CNFAIC Staff Forecaster|
|03/05/21||Turnagain||Observation: Tincan, north side||W Wagner Forecaster|
|03/04/21||Turnagain||Observation: Magnum Peak||Carson Jones|
|03/02/21||Turnagain||Observation: Pastoral||Schauer/ Wunnicke Forecaster|
|03/01/21||Turnagain||Observation: Tincan||Schauer/ Rothman Forecaster|
|02/28/21||Turnagain||Observation: Lynx Creek||Graham --AAS Moto Level 1|
|02/28/21||Turnagain||Avalanche: Tincan||Mike Records|
|02/28/21||Turnagain||Observation: Eddies||Andy Moderow|
|02/25/21||Turnagain||Observation: Seattle flats, above power line||Carly AAS Level 1|
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.