Wind slabs: Over the last few days several wind events combined with over a foot of new snow have created fresh wind slabs up to 20” thick on leeward features. The good news is this new snow is bonding well with the old snow below, however not enough time has passed for this hazard to have completely healed. Wind slabs are likely to be tender and found on slopes steeper than 38°. Trigging an isolated wind slab in the wrong place, like over a cliff or above a terrain trap, could have high consequences. Should today’s visibility allow for easy access into steeper terrain avoid wind-loaded features, watch for shooting cracks, and choose your terrain wisely.
Cornices: Already large cornices have received additional stress over the last 3 days. Strong winds have been adding weight to their robust size and could be extra tender today. These backcountry bombs have a tendency to break farther back than expected and can send you for an undesirable ride. Approach ridgelines with caution and avoid being on or directly below cornices features.
Yesterday’s poor visibility prevented a view into the alpine, but here’s a photo from Tuesday, Jan.19th, of Tincan Proper. Note the large cornice near the ridge and wind-loaded pillow features. Above photo by Aleph J-Bloom
An observation yesterday from Seattle Ridge showed good bonding of new snow and old snow – however tender windslabs are suspect in steep terrain. Photo by Wendy Wagner
In places protected by the wind 12” of loose unconsolidated snow could be fast moving in steep terrain. Loose snow can easily knock a person off of their feet or take them for a ride over a cliff or into a terrain trap. Manage your ‘sluff’ by letting loose snow move past you and avoid terrain features with high consequences.
Today at Treeline (the 1,000’ – 2,500’ elevation band) on all aspects, pay attention to and avoid glide cracks. These can lead to glide avalanches that are very unpredictable as we have seen over the past few days. There is no discernable pattern to predict a failure as they tend to fail naturally and on their own schedule. Warm temperatures can trigger them and so can cooling temperatures. Cracks can form and release in seconds or days later or sometimes a glide crack won’t release at all. The new snow has made it harder to see the existing cracks and glide releases in the terrain.
It is best to give glide cracks a wide berth. Avoid spending time underneath and if skiing or riding in terrain with glide cracks, try and map them out before your travels so as not to end up directly on top of or inside one. Remember, when these do fail, they tend to be destructive, failing to the ground and bringing the entirety of the snowpack with them.
Close up comparision of a glide crack on the East face of Seattle Ridge that released suddenly on Jan.16. These glide releases are now covered with fresh snow and harder to see.
Yesterday 5 € of new snow was recorded at Center Ridge weather station. Temperatures increased into the low 30’s F at 1000′ causing wet heavy snow to fall along the road. Ridgetop winds were light from the Northeast.
Overnight precipitation stopped and temperatures cooled into the high 20’s.
Today expect valley fog in the morning. Skies are expected to be mostly cloudy. There’s a chance of light snowfall by early afternoon. Expect temperatures to increase into the low 30’s F and wind to be light from the Northeast.
|Temp Avg (F)||Snow (in)||Water (in)||Snow Depth (in)|
|Center Ridge (1880′)||30||5||0.5||88|
|Summit Lake (1400′)||31||0||0||27|
|Alyeska Mid (1700′)||n/a||n/a||n/a||n/a|
|Temp Avg (F)||Wind Dir||Wind Avg (mph)||Wind Gust (mph)|
|Seattle Ridge (2400′)||26||n/a||n/a||n/a|
|01/23/20||Turnagain||Observation: TIncan||Eric Roberts|
|01/23/20||Turnagain||Observation: Goldpan||Allen Dahl|
|01/22/20||Turnagain||Observation: Sunburst||Adrian Beebee|
|01/22/20||Turnagain||Observation: Sunburst||Ryan Van Luit Forecaster|
|01/22/20||Turnagain||Observation: Seattle Ridge||W Wagner Forecaster|
|01/22/20||Turnagain||Observation: Tincan||Allen Dahl|
|01/21/20||Turnagain||Observation: Tincan||Eric Roberts|
|01/20/20||Turnagain||Observation: Eddies||H. Thamm B. Edwards|
|01/20/20||Turnagain||Observation: Eddies||Andy Moderow|
|01/19/20||Turnagain||Avalanche: south facing aspect on 3800ft bump just northeast of 4940||Anonymous|
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.