Cornice fall may be one of the larger hazards today with sunshine acting to weaken these already tenuous bombs. Cornices right now are LARGE and UNPREDICTABLE– some bigger than semi-trucks and some with large cracks extending their full length. Yesterday melting snow and dripping water could be seen on cornice faces during the heat of the day along Magnum Ridge. Today the sun will continue to weaken cornices making human triggered (snowmachine or skier) and natural cornice fall more likely in the afternoon. Limiting time spent under these is key and giving them extra room along ridgelines will be necessary. Not only would it suck to trigger a cornice while on top of one, imagine what it would be like if people were also below it. Evaluate all ridgelines and slopes for potential cornice fall and be weary of existing skin tracks and up-routes. There are many areas where the “normal” route is in the line of fire.
Magnum Ridge Cornice – The estabilshed skin track is directly on top of 30-40′ cornice feature.
Same corniced ridge on Magnum. Note the long crack observed on February 18th before a 10 day storm added more weight and stress to this cornice. Photo by Amanda Goss.
Strong winds during a 10-day storm have created layers of wind-affected snow throughout Turnagain Pass. Observations over the last several days have been showing this problem to be stabilizing, however today’s warm temperatures and direct sun could be a catalyst for a human triggered wind slab. Triggering a wind slab is still possible on slopes steeper than 35 degrees especially on slopes with unsupported terrain features. Ease into steeper terrain with caution and avoid solar aspects if you find moist surface snow or see wet loose point releases in motion.
Glide cracks are moving and coming out of hiding after they were covered by wind and snow during the storm cycle. Although it has been several days since the last glide crack we know of released and avalanched, they are still on the move. Limiting time spent under cracks is crucial, as they will mow anything down in their path if one does release.
Very large glide crack on the SW shoulder of Cornbiscuit – view from the Seward Hwy. The entire SW face of Cornbiscuit has extensive glide cracks. Click HERE for more pictures from yesterday.
Yesterday skies were clear and sunny and temperatures reached mid-high 30’s F during the warmest part of the day, around 2pm. Calm winds switched directions mid day from an Easterly direction to a Westerly direction. Overnight skies remained clear and temperatures dropped into the teens to mid 20’s F.
Today Westerly winds are expected in increase slightly 10-15mph along ridgetops. Skies will remain sunny and day time temperatures are expected to spike mid day.
Tomorrow a pattern shift is expected with a possibility of scattered snow showers.
|Temp Avg (F)||Snow (in)||Water (in)||Snow Depth (in)|
|Center Ridge (1880′)||27||0||0||140|
|Summit Lake (1400′)||22||0||0||42|
|Alyeska Mid (1700′)||28||0||0||105|
|Temp Avg (F)||Wind Dir||Wind Avg (mph)||Wind Gust (mph)|
|Sunburst (3812′)||28||NE becoming W||4||10|
|Seattle Ridge (2400′)||24||n/a||n/a||n/a|
|04/21/21||Turnagain||Observation: Sunburst||Schauer/ Behney Forecaster|
|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|
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.