Good morning. This is Wendy Wagner with the Chugach National Forest Avalanche Information Center on Sunday, January 22nd at 7am. This will serve as 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).
The danger will rise to CONSIDERABLE today for wind slab avalanches in areas receiving over 10″ of new snow and moderate to strong winds. Human triggered avalanches will be likely on slopes with recent, or current, wind loading. Storm snow sluffs and soft slabs formed in the new snow will be likely to trigger as well. Careful route finding is advised today as well as steering clear of all runnout zones; slides today could run further than expected.
It seems our 9 day stretch of clear skies, cold temperatures and decreasing avalanche activity has come to an end. As of this morning, new snow and wind has made its way back into our area. Around 8-10″ of light snow has fallen in Turnagain Pass with slightly less in the Girdwood Valley and Summit region. Easterly winds have picked up as well and are gusting into the 30-40mph range.
Today’s avalanche danger is directly related to how much snow and wind the mountains received overnight and how much they will get throughout the day. This is likely to vary from location to location, however, what is not likely to vary as much is the loose faceted snow (our good skiing recycled pow) that was yesterday’s surface. This loose snow will: (1) become a weak layer when overburdened by new snow and fresh wind slabs, and (2) provide additional snow for transport by the winds, increasing the size of wind slabs.
For today – wind slabs will the primary concern. Watch for these to be very ‘touchy’ (as they will be sitting on weak snow) and cracking from your feet or snowmachine. All slopes with recent wind deposited snow should be suspect to slide. Depths of wind slabs will likely vary from shallow and manageable to larger (over a foot deep) and unmanageable. Evaluating these depths, along with the depth of the new snow, will be prudent.
Storm snow sluffing and shallow soft slabs in the new snow will be the secondary concern. These should pack less punch with the light snow, yet are possible to release naturally and likely to be triggered by a person.
A low pressure system that has developed in the northwest Gulf began to spill clouds our way yesterday. Light snow and winds began last night and as of 6 am this morning, around 8-10″ of snow has fallen on Turnagain Pass with 6-8″ in the Girdwood Valley. Winds have bumped up to 35mph on the ridgetops from the east and temperatures have made a shift back to above 0F and are sitting in the single digits below treeline and the low teens above.
Snowfall will continue today and expected to add anCNFAIC Staff 4-8″ (possibly more in the upper elevations and favored areas). Easterly winds are forecast to remain in the 35-45mph range until this afternoon when they should begin to decrease. Expect temperatures to rise into the teens at the lower and mid elevations as the inversion continues to be scoured away.
CNFAIC Weather Page and the NWS forecast
I will issue the next advisory Monday morning. If you get out in the backcountry we want to know what you are seeing. Please send us your observations using the button at the top of this page or give us a call at 754-2369. Thanks and have a great day.