There was one report of a shallow slab avalanche on the Seattle Headwall yesterday. It was triggered by a snowboarder, who was able to ride off the slab. It was on a NE aspect around 3,400′ in elevations. It was reported at 8-12″ deep, 70-90′ wide. (Video HERE).
There was also a report of a large cornice fall in Goldpan (upper Bertha Creek drainage). It is unknown when this occurred, but it looked to be in the past couple days.
Snowboarder-triggered slab referred to above on the Seattle Headwall. Photo Graham Predeger, 4.9.22.
Large cornice fall in the Goldpan area that lies in upper Bertha Creek. Unknown time of release, but most likely during the past two days. Photo by Nick D’Alessio 4.9.22.
|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|
Another brilliant sunny day is on tap with light to moderate northwest ridgetop winds. With several days of generally quiet weather and a generally stable snowpack, we are now in a Normal Caution regime. This doesn’t mean we can turn our brains off though. There are always wintertime avalanche hazards anytime there is snow on the slopes. Bulleted below are the main ways someone could find a mishap.
Shallow slabs on upper elevation northerly aspects: There could be either some lingering wind slabs or a lingering soft slab sitting on a weak layer in these specific areas (high elevation shaded slopes). The snowboarder triggered slab is a perfect example of a small (ish) avalanche that can occur. Even a small slab can have big consequences if it knocks a person down steep rocky terrain or cliffs, for example. Look for those classic signs of wind loading, smooth rounded pillows, hollow feeling snow, and cracking in the snow around you.
Cornice Falls: The recent large cornice fall in Goldpan is a good reminder to really be extra cautious when traveling along ridgelines. These can pull back much farther than one might expect and so we really do have to give them a wide berth. It’s also good to remember that warming temperatures in the afternoon can add to the instability.
Wet loose avalanches: The sun may heat up southerly aspects enough today to melt the top few inches of the surface crusts. It’s that time of year to pay attention to whether or not the surface is becoming wet and saturated. If there are several inches of loose wet snow, it’s time to head to a cooler slope. Wet avalanches are likely to be small today, but could become larger as the week progresses with steadily increasing daytime temperatures.
Glide avalanches: Watch for glide cracks and limit any time under them. We have seen a few glide cracks release into avalanches in the region. There are several cracks along Seattle Ridge, Tincan, Eddies, and elsewhere.
Yesterday: Sunny skies were over the region yesterday with somewhat cool temperatures. Daytime high’s reached the mid 30’sF at low elevations and 20F along ridgetops. Overnight low’s are in the teens. Ridgetop winds were light, 5-10mph with gusts near 20mph at most from the NW.
Today: Another sunny day is on tap, with slightly warmer temperatures. Overnight low’s are again in the teens and should climb to 40F in the parking lots and the mid 20’sF along ridgelines. Ridgetop winds will remain NW in the 5-15mph range with stronger gusts.
Tomorrow: The ridge of high pressure over the area bringing these clear skies should remain through most the work week. Ridgetop winds should remain northwesterly through Monday, then look to be light and variable. Temperatures will be on a steady rise through the week as well.
PRECIPITATION 24-hour data (6am – 6am)
|Temp Avg (F)||Snow (in)||Water (in)||Snow Depth (in)|
|Center Ridge (1880′)||26||0||0||113|
|Summit Lake (1400′)||22||0||0||40|
|Alyeska Mid (1700′)||25||0||0||N/A|
RIDGETOP 24-hour data (6am – 6am)
|Temp Avg (F)||Wind Dir||Wind Avg (mph)||Wind Gust (mph)|
|Seattle Ridge (2400′)||21||NW||5||11|
|05/11/22||Turnagain||Avalanche: Cornbiscuit and Magnum west faces||CNFAIC Staff Forecaster|
|05/07/22||Turnagain||Observation: Granddaddy||Kit Barton|
|04/29/22||Turnagain||Observation: Sunburst wx station||AS/ MM/ AM/ NH|
|04/28/22||Turnagain||Observation: More Turnagain Pass/Summit Lake wet slab activity||Alex Marienthal|
|04/27/22||Turnagain||Observation: Magnum||Sykes / Buttrick Forecaster|
|04/27/22||Turnagain||Observation: Girdwood/Summit/Turnagain Road obs||A S|
|04/24/22||Turnagain||Avalanche: Seattle Ridge – large glide avalanche on Repeat Offender path||CNFAIC Staff Forecaster|
|04/24/22||Turnagain||Avalanche: Seattle Ridge uptrack||Martin Schmidt|
|04/24/22||Turnagain||Observation: Pastoral||Jason Konigsberg|
|04/24/22||Turnagain||Observation: Sunburst||Lance breeding|
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.