Over the last three days 4″ of water fell in the form of rain at lower elevations in Turnagain Pass. Rain/snow line fluctuated between 1800’ and 2500’ leaving the snow saturated with water. Several large wet avalanches were observed along the Seward Highway and Portage Valley over the last two days. Warm temperatures will persist today making it possible to trigger a wet avalanche on steep terrain features. Avoid this hazard by choosing low angle terrain away from large slopes and terrain traps.
*If temperatures drop below freezing this concern will stabilize quickly as water drains and the slab strengthens in the mid elevation zone.
Debris from a wet avalanche in Portage Valley. This avalanche likely released on the morning of Nov.27th.
Strong Northeast winds topped out at 109 mph on Sunburst weather station yesterday morning. Windslabs over 4’ thick on leeward aspects and crossloaded terrain features are a concern for today in the upper elevation zone. Avoid smooth pillow shaped snow on steep slopes and convexities. Even small features if steep enough could break well above you and have plenty of volume to bury a person. Obvious clues like shooting cracks and whumpfing sounds may not be present today making this avalanche problem difficult to identify.
In the upper Alpine above 2500’ weak faceted snow that formed during a cold snap has been covered up by 4’ of heavy snow creating an upside down snowpack. Last week observations showed a large variation in the distribution of this weaker snow below. It is likely that Northern aspects will harbor the bulk of this problem, but until more information is gathered much uncertainty exists as to how well this new snow has bonded with the older less stable snow below it. This is just one more high consequence reason to avoid steep terrain today.
A very wet and warm storm passed through Southcentral Alaska leaving the region with above freezing temperatures and high-sustained winds for multiple days. In Turnagain Pass rain/snow line reached 2500′, Easterly ridgetop winds maxed out above 100mph and 4 € of water fell over a three-day period.
Showery weather in the form of mixed rain and snow is expected today and into the weekend with rain/snow line moving to 1000′. Temperatures will hover just above freezing (32F) and begin to cool slightly by this evening. Easterly ridgetop winds 20-30mph are also expected to depreciate by early evening. This pattern will continue through the weekend with patches of clear sky at times.
*Seattle Wx Station wind data is currently not available.
|Temp Avg (F)||Snow (in)||Water (in)||Snow Depth (in)|
|Center Ridge (1880′)||32F||0||1.4||25|
|Summit Lake (1400′)||33F||0||0.2||10|
|Alyeska Mid (1700′)||34F||0||2.0||13.5|
|Temp Avg (F)||Wind Dir||Wind Avg (mph)||Wind Gust (mph)|
|Seattle Ridge (2400′)||28F||*N/A||*N/A||*N/A|
|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.