Ah, springtime in the mountains. Warm daytime temperatures, longer days (now longer than our friends in the lower 48) and a fresh dose of snow. What more could we ask for? Possibly, a more stable snowpack… Sunday’s refresher storm that brought over 2 feet of snow to the Placer Valley and around a foot to Turnagain Pass and Girdwood fell on a very weak old surface of facets and surface hoar. In areas with greater snow amounts, triggering a slab avalanche is still very possible and even likely. Essentially, the places that are the most enticing for powder lovers (areas with up to 2 feet of new snow) will be the most likely places to trigger a large slab avalanche. In areas with lower snow amounts (a foot or less) triggering a smaller shallow slab is still possible.
There was a report of natural avalanche activity in the Placer Valley yesterday along with one snowmachine triggered slab avalanche. In the Turnagain Pass area, there was one report of a skier triggered avalanche on Magnum. Along with the avalanche activity, we had several reports of whumphing and shooting cracks. Interestingly enough, on our field day over on Seattle Ridge, we had a hard time finding unstable snow. The new snow here was quite shallow (10-12″) and light – just not enough snow to overload the old weak snow surface.
For today, things to keep at the forefront of our minds:
Shallow soft slab avalanche triggered by a skier on Magnum in the Turnagain Pass area yesterday. Photo: Jordan Bancroft
Similar to the slab avalanche concerns above, expect the size of sluffs to be dependent upon the amount of new snow you find. That said, human triggered sluffs (loose snow avalanches) are likely in steeper terrain that were not affected by the sun yesterday. Natural damp or wet loose snow avalanches may still be possible with warming in the afternoon. Keep in mind, sluffs have the potential to initiate a slab lower on the slope.
Dry loose avalanches on the West face of Eddies. Photo: Conrad Chapman
Persistent Slabs and Deep Slabs: There are a variety of very old weak layers in our thin snowpack. The February 9th buried surface hoar sits 2-4+’ below the surface and faceted snow sits in the mid and base of the pack. These weak layers (with varying degrees of strength) have been in a ‘dormant stage’. Although unlikely, an avalanche breaking deeper in the pack isn’t completely out of the question with the new snow load and warming temperatures. Areas such as Johnson Pass, Lynx Creek and on the Northern side of Girdwood Valley (near Crow Pass) are the most suspect and observers continue to find poor structure.
Partly cloudy skies covered the region yesterday. Intermittent light snow showers and cloud cover added a few flakes here and there but no measurable precipitation was recorded at the snow stations. During the past 24-hours ridgetop winds have been light (5-15mph) with moderate gusts (10-25mph) from the East. Temperatures that warmed during the day to 30F at 1,000′ and 25F along ridgetops have dropped back down to the teens overnight.
For today, we can expect another day of in-and-out cloud cover (partly cloudy skies) and no precipitation. Ridgetop winds should remain light 5-10mph from the East and Northeast with a possible bump to the 15-20mph range later this afternoon. Daytime warming will again let temperatures climb into the 25-30F range by the afternoon.
Looking ahead, mostly clear skies with warm days and cold nights is in our future.
|Temp Avg (F)||Snow (in)||Water (in)||Snow Depth (in)|
|Center Ridge (1880′)||18||0||0||65|
|Summit Lake (1400′)||19||0||0||30|
|Alyeska Mid (1700′)||23||0||0||61|
|Temp Avg (F)||Wind Dir||Wind Avg (mph)||Wind Gust (mph)|
|Seattle Ridge (2400′)||20||6||SE||19|
|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: email@example.com
|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.