Bitter cold temperatures have been present the last 48 hours and will continue through today. Moderate to strong winds have been ranging from Northwest to Northeast with the cold frontal passage, so touchy wind slabs will be present at the mid and upper elevations on leeward slopes. If triggered in shallow areas of the snowpack an avalanche may have the potential to stepdown to the deep persistant weak layer of facets and rain crusts. The primary concern today is still the frigid temperatures and high consequences if injured or caught out in the elements, so if you venture out into the backcountry today make conservative decisions!
Wind slabs are likely to be triggered at the mid and upper elevations today due to moderate to strong winds throughout the past 48 hours. Be aware of surface conditions and listen for hollow sounding snow, cracking and collapsing.
In steep, sheltered terrain dry loose avalanches are likely in the low density snow that has recently fallen. These dry loose sloughs may seems innocent and manageable, but can cause you to lose control and strain you through trees and rocks.
The persistant weak layer near the base of the snowpack is less reactive as the weeks go by, but could still be triggered in a step-down avalanche or in areas where the snowpack is thin and void of vegatation and anchors. This weak layer will remain a concern through much of the winter, so stay alert and cautious!
The frigid temps prevented us from going into the backcountry to get observations yesterday.
The past few days the cold front winds came from the north and east, which typically loads snow onto sides of the mountain that are generally more scoured and weak under our normal southwesterly weather flow. This "reverse loading" catches many riders off gaurd. Watch out for snow that is cohesive enough to crack or support your weight as it is likely a slab that is poorly bonded to the snow below it. Friday, winds wil shift to the South and Southeast which means wind slab may develop on multiple aspects.
My second concern would be loose-dry sloughing in steep terrain. If you choose to drop into steep terrain, it is possible that you will generate lots of loose snow flowing down the hill with you. Though not as dangerous as a slab avalanche these small avalanches can cause you to lose control and slam you into trees, rocks, etc. You can't afford an injury today with below zero temperatures. Staying on your feet and moving is imperative to your survival in these conditions.
Lastly, we continue to keep an eye on our persistent weak layer close to the ground that consists of crust and sugary snow. We are seeing less reactivity out of it with each passing week, but the variability of this layer still concerns me. I would exercise caution in choosing terrain this week. Steep and unanchored slopes that lack vegetation are suspect. I would also be wary of areas where the snowpack is thin and the weak layer is closer to the surface. These are the kind of spots where this weak layer may be triggered.
The weather will warm up Christmas day and through the coming week with more snow in the forecast. Expect avalanche conditions to rise as dense, heavy snow falls atop the low density snow from this past week creating an upside down snowpack. Warm air and potential rain is forecast into Monday and Tuesday. We will be watching this change closely as we may see a big shift in avalanche conditions at lower elevations in the coming days. Stay tuned!
There is still room in IPAC's Level 1 motorized avalanche classe! Follow the link for details: https://www.idahopanhandleavalanche.org/friends-ipac-avalanche-safety-courses
Also, you should check out or new "Observations" platform thanks to the fund raising efforts of our Friends group and Board Member Mike Brede!
