Our primary concern continues to center around glide avalanches. These are popping out both small and large over the past several days. They are mostly in the mid-elevation band and the warm weather has kept them active. The last known glide crack to release on Turnagain Pass that we know about, releasing in areas people recreate, was two-three days ago on Eddies Ridge. The only way to manage this avalanche problem is to limit, or avoid, time under glide cracks.
Photo below: Glide cracks and one release on Peak 3640′ just Southeast of Gilpatrick in the Summit Lake zone.
Over the past two days we have seen 1.5+” of rain fall up to 2,500, possibly higher in some areas; this is the highest rain line we have seen this season. Yesterday afternoon temperatures at treeline (2,400′ on Tincan) reached 34 degrees! The snowpack is slowly decreasing at the mid-elevations, but there is still plenty to ride out this warm spell.
Wet avalanches continue to be a concern. With little visibility yesterday we are uncertain as to the extent of any natural wet activity. As the temperatures remain warm, the rain-on-snow will continue to weaken the snowpack and naturally occurring wet loose, and even some wet slabs avalanches, are possible. These slides can be quite large on sustained slopes such as the East face of Seattle Ridge. Steering clear of runnout zones will be key if you are getting out today.
Left photo: Tincan Ridge, still plenty of snowcover despite the rain. Right photo: The motorized lot is slick but has been plowed out nicely.
At the high elevations where it is snowing (this is above 2,500′) there are a variety of storm snow avalanche issues:
Storm Slabs: This warm, wet snow should bond quickly to the surfaces below but the warmer snow over slightly colder snow may create storm slabs. Quick hand pits are a good way to determine if the new snow is sticking to the old snow.
Wind slabs: Over the past two days we have received 15-20″ of new snow with sustained winds. Although wind slabs are stabilizing quickly with the sticky snow, it may still be possible to trigger a wind slab in steep wind-loaded terrain. Be on the lookout for stiff, pillowed snow and shooting cracks.
Cornices: The fresh snow/wind combination will also add to already large cornices that may be very tender due to warm temperatures. Avoid travel on or below these behemoths.
Yesterday was another mostly cloudy day with rain falling off and on at the Pass. Around .5″ of rain fell up to 2,500′ with ~5″ of wet snow above this. Ridgetop winds were strong to moderate through the day from the East and were blowing in the 20-35mph range. Temperatures were warm….up to 35F at 2,000′. This is all due to a series of low-pressure systems moving over us and entraining warm and moist air from the South.
Overnight, light precipitation has continued and temperatures have remained warm. The rain/snow line looks to have dropped slightly to 2,000′. Another shot of precipitation and wind is on tap again today. It has been difficult determining how much precipitation will make it over the mountains from PWS, but so far we seem to get a bit more than forecast. We may see up to .5″ today and another .5″ tonight, with the rain/snow line between 1,800 and 2,000′ (equating to another 5-10+” in the Alpine). The Easterly ridgetop winds should pick up again to the 25-35mph range with stronger gusts.
For Sunday, this warm and wet weather pattern looks to continue.
|Temp Avg (F)||Snow (in)||Water (in)||Snow Depth (in)|
|Center Ridge (1880′)||33||rain||0.5||105|
|Summit Lake (1400′)||35||rain||0.1||30|
|Alyeska Mid (1700′)||34||rain||0.6||86|
|Temp Avg (F)||Wind Dir||Wind Avg (mph)||Wind Gust (mph)|
|Seattle Ridge (2400′)||28||–||–||–|
|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: 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.