|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|
Yesterday there were 3 reports of skiers and snowmachiners triggering avalanches across the region. A party of skiers triggered two avalanches on Sunburst, one on a deeper buried weak layer. The skier involved in the deeper avalanche was caught, carried, deployed their airbag and ended up off of the debris. A snowmachiner remotely triggered a slab in Grandview and a skier remotely triggered a slide from the skin track in Summit Lake. Today triggering a large and unmanageable slab avalanche 2-4′ thick remains our primary concern. Various layers of old faceted snow and buried surface hoar sit under the 2-4 feet of storm snow from Friday. These persistent weak layers have been well documented and are wide spread across our region. During the window of sunshine yesterday some folks ventured out into steeper terrain with no incident while at the same time others were triggering avalanches. Recreating in steeper terrain is a gamble at this point with high consequences if the house wins…
If you are headed out into the backcountry today things to keep in mind are:
Sunburst avalanches from below. Photo: Conor Roland
Sunburst avalanches from a different view. The upper one is harder to pick out.
Grandview avalanche that was triggered from below, lookers left side. Photo: Sebastian Landry
Remotely triggered avalanche in Summit Lake. Photo Patrick McCormick
Loose Wet Avalanches: Several inches of low-density snow fell this weekend. Wet snow or rain falling could trigger loose wet avalanche activity especially at lower elevations. Radiation from the sun, if it clears later in the afternoon, could also be factor today. Look for small loose wet sluffs on Southerly aspects in steep rocky terrain. On upper elevation slopes unaffected by rain, wind or sun loose dry avalanches (sluffs) are also possible in steep terrain.
Wind slabs: Shallow wind slabs formed on some leeward features yesterday due to moderate Easterly winds in the Alpine. Triggering a wind slab will likely be shallow, but could step down to a deeper layer of the snowpack and create a much larger and more dangerous avalanche.
Cornices: Cornices have grown and are suspect for breaking while traveling along ridgelines. Give these an extra wide berth and minimize any time below them. Cornice falls can trigger avalanches on slopes below.
Natural loose wet activity on Seattle Ridge in the afternoon yesterday.
Yesterday was mostly cloudy in the morning and became mostly sunny by the mid to late afternoon. Temperatures were in the 20Fs to low 30Fs. Easterly winds were blowing 5-15 mph gusting into the 30s in the morning and calmed down in the afternoon. Overnight temperatures cooled slightly and then started rising in the early morning. Clouds moved in and Easterly winds were light.
Today will be mostly cloudy with snow/rain showers, 1-4″ of snow possible and rain below 800′. There is a chance of some clearing in the late afternoon. Temperatures will be in the high 20Fs to high 30Fs. Winds will be Easterly 5-15 mph with gusts into the 20s. It is forecast to be mostly cloudy overnight with a chance of snow showers.
Tomorrow looks to mostly cloudy in the morning with clearing in the afternoon, light Northwest wind and temperatures in the high 20Fs to mid 30Fs. The next system moves into the area Thursday. Timing and details are still uncertain.
*Seattle Ridge anemometer (wind sensor) rimed over and not reporting
|Temp Avg (F)||Snow (in)||Water (in)||Snow Depth (in)|
|Center Ridge (1880′)||29||1||0.1||90|
|Summit Lake (1400′)||27||1||0.1||36|
|Alyeska Mid (1700′)||28||1||0.12||82|
|Temp Avg (F)||Wind Dir||Wind Avg (mph)||Wind Gust (mph)|
|Seattle Ridge (2400′)||23||n/a*||n/a*||n/a*|
|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: 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.