Lots of avalanches of different character today (loose dry, wind slabs, deep persistent), and although some were size 2.0, there was generally nothing really big. Conservative terrain choices will help avoid these problems.
Weather Forecast
Wednesday will be mostly cloudy with light flurries. Winds will be light to moderate from the NE and temperatures should climb to -9 by the afternoon. Very light flurries expected Thursday and Friday.
Avalanche Summary
Recent strong winds resulted in several loose dry avalanches up to size 2.0, primarily in very steep Alpine terrain on all aspects. In addition, the deep persistent layer of basal facets finally woke up and a size 2.0 naturally triggered slab occurred on the north end of Tent Bowl around midday today. This slide occurred at Treeline and was only about 40m wide, but was between 120 and 140cm deep and failed on the basal facets. Avalanche control today on EEOR resulted in another full depth avalanche that deposited large amounts of debris on HWY 742.
Snowpack Summary
Alpine and Treeline areas suffered some wind damage in the past 24 hours, and there are now fresh wind slabs in some of this terrain. Typical lee and cross-loaded features will have wind slabs, but reverse wind-loading can also be expected due to recent N and NW winds. The late February sun is now powerful enough to create sun crusts on some steep solar aspects, but cold temperatures have been reducing this somewhat. The mid pack has enough strength and depth (in most places) that triggering the bottom layers is becoming more difficult. The key to avoiding trouble is avoiding thin areas where the bridging is minimal.
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.
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.
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.