Winds today caused a rapid spike in hazard that will carry over into tomorrow. Re-align your sites for more conservative objectives. Hazard ratings account for avalanches running further than expected.
Confidence
Moderate - Wind speed and direction is uncertain
Weather Forecast
For most of the night temps will be around -13. In the early morning expect them to drop a few more degrees. Settling at -18 by 8am. UP to 4cm is expected from flurries. Winds...if it wasn't for wind, we'd no weather discussion at all. They should be from the SW tonight, but at midnight they're expected to pull a 180° shift and blow from the NE. If that weren't enough, by noon tomorrow they'll shift to the south. The good news is that they'll be diminishing as these shifts happen.
Avalanche Summary
A big day for avalanches:-numerous loose dry "facalanches". Many seemed cornice triggered and carried surprisingly far; entraining deeper layers as they went. Healthy sz2's. They are more concentrated to the northern part of the region-A group reported a sz2 on the traverse towards the north side of Hero's Knob. Its unknown exactly what triggered it, but it did carry a skier away for a short distance. E aspect at about 2300m.-Numerous thin slabs around the bottoms of large alpine cliffs-Tent Ridge (surprised?) went sz 3 on its eastern aspect mid day today. A cornice triggered a loose dry which in turn triggered the deep persistent layer.
Snowpack Summary
Interesting day today. To sum up the observations, its fair to say the snowpack is changing and the relatively solid snowpack is taking a turn for the worse. The winds picked up last night and instead of changing to a westerly flow, they held a northerly direction and lingered for the better part of today. This made for a rapid reverse loading pattern in the alpine. Lots of spindrift made reactive windslabs around cliffs. Treeline didn't escape the wind either. Slabs are there, but not as thick or dense as higher up. In an untracked, rocky, thin treeline area we had shooting cracks of up to 20m and large settlements. Remoting avalanches suddenly seemed like a real possibility. Open, below treeline areas also had large settlements on the Jan 17 surface hoar. The solar input is strong enough to soften the snow. The warming trend and wind loading is to blame for this rapid decrease in stability.
Problems
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
Deep Persistent Slabs
Deep Persistent Slab avalanches are the release of a thick cohesive layer of hard snow (a slab), when the bond breaks between the slab and an underlying persistent weak layer deep in the snowpack. The most common persistent weak layers involved in deep, persistent slabs are depth hoar or facets surrounding a deeply buried crust. Deep Persistent Slabs are typically hard to trigger, are very destructive and dangerous due to the large mass of snow involved, and can persist for months once developed. They are often triggered from areas where the snow is shallow and weak, and are particularly difficult to forecast for and manage.
Loose Dry
Loose Dry avalanches are the release of dry unconsolidated snow and typically occur within layers of soft snow near the surface of the snowpack. These avalanches start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-dry avalanches include point-release avalanches or sluffs.