|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|
This morning, skies are clear, winds are light from the east and temperatures cold. This morning also marks the 16th day of the January drought. During this dry spell, winds have been generally northwesterly and impacting ridgelines and peaks north of Girdwood, through Turnagain Arm and Portage Valley and south of Johnson Pass. The heart of Turnagain Pass has been spared much of the wind. Although there are various weak layers in the snowpack that were causing grief earlier, the slab on top of them is being slowly eaten away (faceting) and triggering an avalanche in one of these old buried layers is unlikely. What is more of a concern is finding a wind slab that was formed over the past week or so that is sitting on weak faceted snow. With the variable wind effect in the region, don’t let the green danger rating keep you from being observant and sticking with your safe travel practices. Until a change in weather arrives, we are in a Normal Caution avalanche regime, meaning there are still issues to watch for listed below.
Some wind effect in the higher terrain on the southern end of Seattle Ridge at Turnagain Pass. 1/15/20.
Wind slabs on weak snow: If you are headed to the steeper and higher elevation terrain, be on the lookout for wind affected snow. Watch for pillowed snow surfaces, feel for hollow feeling snow and generally speaking- stiffer snow over softer snow. Cracks that shoot out from you are a red flag as well as whumpfing (collapsing) of the snowpack. Even a small wind slab can be dangerous if it knocks a person off their feet and down a rocky slope.
Loose snow sluffs: The surface snow is so loose and faceted it is very easy to initiate a sluff in steep terrain. These sluffs have been catching a few folks off guard. They can be quite heavy and gain more volume than one might expect. If heading to steep chutes or slopes, sluffs should not be underestimated.
Glide cracks: Despite the frigid temperatures, glide cracks continue to ooze open. It’s always a good idea to limit any exposure under them as they can release at any time.
Cornices: We have had no reports of cornice failure for some time, but we still need to give them a wide berth.
Glide cracks on the northern most portion of Tincan, just above Todd’s Bowl. 1.17.20. Photo: Allen Dahl
Snowpack update: This graph shows the snow depth from the past 30 days at 1,880′ at the Turnagain Pass SNOTEL. After around 2 feet of snow fell during the holidays, for a total snow depth of 46 inches, the depth has decreased (settled) almost a foot over the past 16 days and now sits at 36 inches. Note: there was a short pulse of moisture on Jan 13th that did add 1 inch of snow during the dry period. Also of note, the snowpack is just under half of what it normally is this time of year.
Yesterday: Mostly sunny skies were over the region with a few clouds filtering through. Ridgetop winds remained from the east and bumped up into the 10-15mph range in the afternoon before quieting back down to around 5-10mph overnight. Temperatures were again inverted with upper elevations in the 10-15°F range and valley bottoms -20 to 0°F. Overnight, the inversion has remained in place.
Today: Mostly sunny skies will prevail for one more day with a few clouds possibly moving in this afternoon. This morning, Ridgetop winds are light from the east and temperatures sit near 0°F in valley bottoms and around 10°F at the higher elevations. Winds are forecast to remain light through the day and tonight, in the 5-10mph range from the east. Temperatures should again rise into teens at all elevations during the day and remain above 0°F overnight.
Tomorrow: Clouds will continue to move in tomorrow ahead of a low-pressure system forecast to push in from the Gulf Sunday night into Monday morning. Winds should be on a slight rise tomorrow afternoon from the east and a trace to a few inches of low density snow (to sea level) is forecast for Monday into Tuesday.
PRECIPITATION 24-hour data (6am – 6am)
|Temp Avg (F)||Snow (in)||Water (in)||Snow Depth (in)|
|Center Ridge (1880′)||15||0||0||36|
|Summit Lake (1400′)||3||0||0||15|
|Alyeska Mid (1700′)||14||0||0||36|
RIDGETOP 24-hour data (6am – 6am)
|Temp Avg (F)||Wind Dir||Wind Avg (mph)||Wind Gust (mph)|
|Seattle Ridge (2400′)||13||SE||7||17|
The Seattle Ridge weather station ‘south view’ web cam shows some clouds moving in yesterday (Friday) evening ahead of a weak low-pressure system slated to move through Sunday night.
|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.