More human triggered avalanches occurred yesterday with reports coming in from both Tincan and Sunburst, including the slope below Taylor Pass sliding. The buried layer of surface hoar continues to be the problem layer. It sits below the new snow from Thursday and has a few additional inches added from the weekend. Slabs have been soft and releasing while people are riding them as well as being triggered remotely from above or the side. With all the snow available for transport and an increase in wind speeds last night the slabs could be even more developed today, stiffer and more hazardous. Slab depths near ridgelines and in leeward areas could be deeper. Look for cracking in the snow, whumpfing and recent avalanche activity. Low angle slopes have been releasing which is a common with buried surface hoar. Pay attention to slope angle and what the terrain you traveling on is connected to, above and below. Avalanches were triggered onto and close to the skin track on Tincan both Saturday and Sunday. Please think about where you put skin tracks in and when you are descending make sure you are not skiing or riding on top of other people.
The new snow and wind will also make it harder to tell what slopes have slid already and wind slabs may be sensitive and exacerbate the problem. Today is another day to be conservative. Remember the buried surface hoar is widespread and is a persistent weak layer. This means it doesn’t heal/settle quickly and can be reactive for extended periods of time.
Backlit cross section of snow on Sunburst that shows the buried surface hoar. Photo W. Wagner
Looking up the skin track towards Tincan Common. Low angle avalanche from Saturday below the skin track.
The winds have ramped over night gusting into the 40’s from the ENE. The light fluffy snow that we have enjoyed over the weekend will easily blow around and create fresh sensitive wind slabs that may or may not be sitting on the buried surface hoar. Wind slabs could be reactive either way and may make the slopes with surface hoar even more prone to avalanche. It will be important to pay attention to how the snow feels underfoot. Is it stiff? Does it feel upside down i.e. hard over soft? Do you see shooting cracks? Does it feel or sound hollow? Look for recent cornices, wind pillows and drifts. Remember recent wind is a RED FLAG and means something has changed. This is another reason to be conservative today. How are the mountains channeling the winds? Are slopes being wind loaded? Can you tell if the slopes are top loaded or cross loaded? Has the wind blown and affected the snow in the trees?
Photo: National Avalanche Center
Yesterday was mostly cloudy with snow showers and a few windows of clearing. The winds were light and temperatures were in the low 20Fs. Overnight the winds picked up from the ENE blowing in the 20s and gusting into the 40s. Temperatures rose to the high 20s. 2-5 inches of snow fell in the last 24 hrs.
Today will be mostly cloudy with a chance of snow showers tapering off in the afternoon. 0-2 inches of snow possible. Winds will be in the 20s and gusty. These should also taper off during the day. Temperatures will be in the high 20Fs.
There is a clearing trend Tuesday into Thanksgiving Day with sunshine forecasted, light winds and temperatures in the 20Fs. An unsettled pattern returns over the weekend with a chance of snow.
|Temp Avg (F)||Snow (in)||Water (in)||Snow Depth (in)|
|Center Ridge (1880′)||27||5||.4||21|
|Summit Lake (1400′)||27||1||.1||3|
|Alyeska Mid (1700′)||28||2.5||.2||5|
|Temp Avg (F)||Wind Dir||Wind Avg (mph)||Wind Gust (mph)|
|Seattle Ridge (2400′)||23||N/A (sensor rimed)||N/A (sensor rimed)||N/A (sensor rimed)|
|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.