Skookum Valley: A skier remotely triggered an avalanche 150’ wide and 3’ deep that ran 200 vertical feet on a NE aspect at 800’ elevation. Nobody was caught or carried. (more details)
Grandview: A skier remotely triggered a small but deep wind slab on a convex rollover at around 1500’ elevation on a west aspect. The pocket that released was about 40’ wide and 1.5-3’ deep, running for about 40 vertical feet. The slab failed on a weak layer of buried surface hoar on top of a melt-freeze crust. (more details)
|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|
Moderate avalanche danger covers a wide range of avalanche conditions, and today’s avalanche problem should not be taken lightly. The midweek storm brought 1-2’ of snow, burying a weak layer of faceted snow and surface hoar. Subsequent winds on Thursday and Friday have drifted this snow into stiff wind slabs up to 3’ thick or thicker, and we have seen multiple skier-triggered avalanches as a result (details here and here). Today’s combination of weather and snowpack is the exact situation where most avalanche accidents occur. A sunny weekend day with conditionally unstable snow (ready to avalanche on some slopes and stable on others) will make it easy to get lulled into a false sense of security. Here are a few things to think about to keep you out of trouble today:
Just like we saw last month, these persistent weak layers will need some time to gain enough strength to be trusted. For now, the safe bet is to recognize the increased hazard and take a step back in your terrain use.
Sluffs: Steep slopes that have been sheltered from the wind have around a foot or more of loose snow sitting on top of firm surfaces. It will be easy to trigger dry loose avalanches today, and they can pick up enough volume and speed to carry a person. While it is unlikely they will be big enough to bury you, they can be dangerous if they drag you into terrain traps like cliffs, trees, rocks, or gullies.
Yesterday: We had plenty of sunshine yesterday, with clear skies and cool temperatures. High temperatures were in the single digits to upper teens F, with overnight lows down to -12 F near Summit Lake to just barely above 0 F in Girdwood and on Turnagain pass. Westerly ridgetop winds were sustained at 5-15 mph, with gusts to around 20 mph.
Today: Another day of clear skies and chilly temperatures is on tap today before active weather returns tomorrow. Highs are expected in the single digits to upper teens F, with lows in the single digits above and below 0 F. Westerly winds are expected to gradually decrease during the day, blowing 5-15 mph at ridgetops this morning.
Tomorrow: Cloud cover will increase early tomorrow morning, with the highest chance of precipitation late afternoon Sunday to early Monday morning. Winds will shift back to the southeast at 10-15 mph with gusts to 25 mph, and high temperatures are expected in the mid to upper teens F. Total snowfall is looking a bit more modest than our last storm, with around 6” expected by Monday morning. Stay tuned for updates!
PRECIPITATION 24-hour data (6am – 6am)
|Temp Avg (F)||Snow (in)||Water (in)||Snow Depth (in)|
|Center Ridge (1880′)||9||0||0||116|
|Summit Lake (1400′)||2||0||0||45|
|Alyeska Mid (1700′)||9||0||0||119|
RIDGETOP 24-hour data (6am – 6am)
|Temp Avg (F)||Wind Dir||Wind Avg (mph)||Wind Gust (mph)|
|Seattle Ridge (2400′)||5||N||3||10|
|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|
|04/10/21||Turnagain||Observation: north sides||lance breeding|
|04/09/21||Turnagain||Observation: Girdwood to Turnagain Road Observations||W Wagner Forecaster|
|04/05/21||Turnagain||Avalanche: Resort bowl Seattle creek head wall||Clint Kyffin|
|04/04/21||Turnagain||Observation: Center Ridge||Andy Moderow|
|04/03/21||Turnagain||Observation: Repeat Offender – Seattle Ridge||Troy Tempel|
|04/02/21||Turnagain||Observation: Seattle Ridge||Wagner / Schauer Forecaster|
|04/01/21||Turnagain||Observation: Pete’s||Schauer/ Cullen 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.