The storm snow that makes up our primary concern started falling on Monday. It tapered off substantially yesterday and transitioned to rain below 1000 feet. All told, more than 2 feet of new snow fell from this storm. Combined with a lot of wind, we have scoured areas between heavy wind loading.
Yesterday we were finding the storm snow would break easily on the new snow/old snow interface. This is the old surface layer about an inch above the late February crust. This is a very easy interface to identify, no need to pull out the shovel, just dig in with your hand to find it. Any avalanches today are likely to break a little above that crust, taking 2 feet of storm snow or greater amounts in wind loaded areas. Areas with now buried surface hoar may behave even worse with a persistent weak layer involved.
I’ll mention that avalanche activity yesterday seemed a bit sluggish – initiation was slow and avalanches were somewhat small in size for the amount of snow we got. This doesn’t mean much in terms of travel advice… It’s still an easy call when managing today’s problem. A lot of new snow on top of a crust with sporadic buried surface hoar – requires conservative travel in the backcountry.
Below 1000 feet we did get rain at the later half of this storm. The lower you go, the more rain we got. This isn’t a big concern, just keep in mind that lower elevations have a water saturated surface layer.
The recent storm is the big news. Storm totals listed below. Numbers are 48 hour snow totals. Keep in mind that the snow is settling and temperatures increased during the storm, transitioning to rain at lower elevations.
Girdwood midway – 26″ (2.25″ water equivalent)
Turnagain Pass – Center Ridge – 25″ (2.2″ water equivalent)
Summit Lake – 12″ (1″ water equivalent)
Wind blew hard during the peak of the storm, which caused visually evident scouring of ridges. Max gusts were recorded up to 114mph at ridge tops. That wind diminished yesterday.
Today will bring a short break in precipitation intensity. Snow and rain showers are expected throughout the day with an inch of accumulation. Wind is increasing through the day as another weather front approaches.
Tonight and tomorrow will bring another storm similar to the last one. Predicted snow totals for tonight and Thursday are 14-24 inches. There is a high wind warning in effect 2am to 8am Thursday for Turnagain Arm and Portage.
|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.