When figuring out how weather influences avalanches, we need to look at three main factors: precipitation, temperatures, and wind. Today temperatures will be the factor to pay the most attention to. Closely related to temp, and requiring your attention today, will be the sun. We have begun a melt freeze cycle around here. While this is a trend that generally encourages the stabilization of the snowpack, there is a critical period during the day when the snowpack de stabilizes. It’s during these times when it is important to move off of terrain to avoid avalanches. Paying attention to the surface snow and how deep your sled or skis penetrate is the best tool for recognizing this hazard. The further you are sinking in, the greater the volume of an avalanche will be. Looking for rollerballs and pinwheels is another way to anticipate wet avalanche activity. We received mutlple reports of natural wet avalanches in the mid and lower elevations yesterday. Both the sun and ambient air temp will help to weaken the snow surface and allow for humans to trigger low to medium volume wet loose and potentially wet slab avalanches today.
These giant masses of snow dangling above many South, Southwest and some West facing slopes will be tested by the sun and warm temperatures today. Today is not your day to tempt fate. While it will be easy to figure out what is happening when you are near cornices (i.e. on ridgelines), it is a whole other story when that cornice is a thousand or more feet above you. When traveling up valleys today it will be best to treat any slope receiving direct sunlight with suspicion. Having groups spaced out to minimize exposure and not stopping directly below cornices, even if they seem far away, will be your best way to manage this problem today.
(Old) Wind Slabs
There remains a chance for finding a lingering pocket of wind slab in steep upper elevation starting zones today. Wind slab avalanche activity peaked on Friday/Saturday, over two days ago, and remains a (lower level) concern.
In the past 24 hours the mountains around eastern Turnagain Arm have experienced warm temperatures, with the Sunburst weather station (3,812′) averaging 22.6 degrees F and the freezing level climbing to the ~2,500′ elevation. Winds at Sunburst have been light, averaging 3mph out of the East with gusts to 12mph. Precip ended in the morning hours yesterday and totaled 6″ of snow in the Girdwood Valley and just a trace on Turnagain Pass.
Today expect a similar day to yesterday, with rising temperatures and sunlight being the main weather factors to incorporate into your terrain selection. Temperatures at 1,000 feet will be in the 35-40 degree range. Winds out of the north will be light, in the 5 to 10 mph range and will minimally help to lessen the effects of the sun and warm temps today.
The extended outlook calls for continued mild temperatures, sunshine and no precip until the end of the week.
Wendy will issue the next advisory tomorrow morning, April 2nd.
|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|
|04/15/21||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|
|04/10/21||Turnagain||Observation: north sides||lance breeding|
|04/09/21||Turnagain||Observation: Girdwood to Turnagain Road Observations||W Wagner Forecaster|
|04/05/21||Turnagain||Avalanche: Resort bowl Seattle creek head wall||Clint Kyffin|
|04/04/21||Turnagain||Observation: Center Ridge||Andy Moderow|
|04/03/21||Turnagain||Observation: Repeat Offender – Seattle Ridge||Troy Tempel|
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.