Good morning. This is Wendy Wagner with the Chugach National Forest Avalanche Information Center on Thursday, March 8th 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).
We have a LOW avalanche danger in our core Turnagain Pass zone. Though the danger is LOW there are still some avalanche concerns to watch out for: 1 – isolated wind slabs in exposed upper elevation terrain, 2 – small dry snow sluffs and a chance for wet point release avalanches, and 3 – glide avalanches. Keep your avalanche eyeballs open as LOW still means avalanches are possible in just the right place, especially areas outside our core zone.
It was anCNFAIC Staff brilliant, sunny day in the backcountry yesterday. A sun crust sits on most southerly slopes with northerly aspects sporting soft settled powder. Small surface hoar has developed from valley bottoms up to ridgelines in certain areas. Avalanche activity yesterday continued to be relegated to small human triggered sluffs and a few wet point releases on southerly aspects. We did not hear of any wind slabs popping out, but these little dragons are suspected to be out there is just the right spot.
Primary concern: Wind Slab
Lingering wind slabs are becoming harder to trigger but still exist in upper elevation exposed terrain where wind loading/cross loading has occurred. As folks press further and further into the backcountry and into extreme terrain, these become more likely to find, trigger, and due to the nature of the terrain, can knock you somewhere with very bad consequences. The pack is generally deep and stable but stubborn shears still exist under these wind slabs – this observation points out what we have been finding as well. Additionally, if the northerly winds increase more than predicted today (more than 15mph) watch for any small fresh slabs forming on southerly aspects.
Secondary concern: Loose Snow
Moist point release avalanches are still possible on the southern half of the compass. These are less likely to release naturally due to the snowpack seeing the sun for a couple days, however they are still possible to be triggered by a person.
Dry snow sluffing should continue on steep slopes that have not formed a sun crust. Any person steeping up their exposure into steep and extreme terrain should expect to trigger these and have a plan to manage them.
Yesterday a glide avalanche released on a lower elevation, northerly aspect in the Skookum Valley and came too close for comfort for the snowmachiners nearby – photos HERE. These unpredictable avalanches can release any time of year. This is a good reminder to always keep an eye out for glide cracks and limit any time around and under them (in the photos you can see one of these cracks above the avalanche).
Sunny skies, mild temperatures and calm to light winds kept the sunscreen out yesterday. Temperatures hovered around the upper 20’s below treeline and in the teens above. Winds were dead calm to variable up to 5mph.
Today we have similar weather in store. There are some mid to high clouds over our area this morning but these should filter out today giving us mostly sunny skies again. Temperatures have plummeted to the single digits overnight but will rebound back to the 20’s below treeline and the teens above. Winds have just turned to the north this morning where they are forecast to blow 5-10mph with gusts to 15mph on the ridgetops.
There is a low pressure system spinning in the Gulf that looks like it will skirt to the east of us but may bring a chance for a flake or two Friday.
CNFAIC Weather Page and the NWS forecast
Kevin will issue the next advisory Friday 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.