Turnagain Pass Avalanche Forecast

An increase in wind with a few inches of snow (to sea level!) is in the forecast beginning this afternoon. Winds should start picking up around noon, but are not expected to be strong enough to transport snow till around sunset. A few snow flurries could fall today, but the heavier snowfall is expected overnight. The increase in avalanche danger will be directly related to the amount of wind and snowfall.

In the high Alpine, above 3,000′, there is still concern over a weak layer of snow sitting near the base of the snowpack. This is greater where the overall snowpack is shallower- towards the southern end of Turnagain Pass, in Summit Lake and in the Crow Pass terrain north of Girdwood.  The weak layer is buried anywhere from 1 – 6+ feet deep due to the extensive variable wind during the early to mid-Dec storm cycles. There is still a lingering concern that a person could trigger a large avalanche at the high elevations above 3,000′.

NORMAL CAUTION avalanche issues during the daylight hours, before the winds and snow arrive:

Cornice falls:  Large cornices have formed in the alpine along some ridges and gullies.  A ‘cornice crevasse’ was found yesterday, check out the photo below. Give cornices a wide berth and limit exposure under them.

Lingering and possible new wind slabs:  Watch for lingering older wind slabs that may not be well bonded with the snow underneath. As winds are predicted for this afternoon, new wind slabs could form, yet this may not materialize until after sunset.  Small wind slab failure can easily force a person off their feet down the fall line. Use caution when traveling above higher consequence terrain (such as cliff bands and rocky areas).

Loose snow sluffs:  The surface snow is loose in steep terrain.  Remain mindful when traveling above cliffs and rock bands.

Large cornice crevasse was found and pictured by Adrian Beebee along the Magnum Ridgeline. These cracks happen when the cornice peels away from the ridge yet has not fallen or may be supported by the slope below. Size was estimated at 6′ wide and 12′ deep – yipes!!

Looking forward to a new layer of snow tonight and into the week:
Our current snow surface is now covered with feathers of surface hoar – it appears to widespread through the region. This is a notorious weak layer once it becomes buried…

Solstice Surface Hoar:  The past few days of cold clear weather produced this crop of surface hoar on Tincan with Sunburst in the distance – possibly a future weak layer. Thank you to Troy Tempel for the photo!

Keep your eyes peeled for glide cracks in the terrain that you are traveling in. Steer clear and avoid lingering in the runout of this unpredictable hazard. There is a chance we may see some more glide cracks open and release as temperatures slowly rise.