Light snowfall and strong winds were a factor again on Monday but natural avalanche activity is declining. Careful evaluation of terrain will certainly be necessary over the next couple of days as light snowfalls and strong winds will continue.
Confidence
Fair - Wind speed and direction is uncertain
Weather Forecast
Cloudy with scattered flurries on Tuesday. Precip 5-8cm snow. Overnight low -13 , daytime high -9. Winds West 25 km/h gusting to 65 overnight and 35km/h gusting to 70 km/h on Tuesday.
Avalanche Summary
Visibility was limited by cloud cover and light snowfalls but natural avalanche activity appears to have tapered off on Monday as the storm snow settled and new snowfall amounts have declined. The moderate to strong winds will further develop and stiffen the variable thickness windslabs which have formed over the past few days. With the exception of some loose dry sluffs originating in steep rocky terrain, no new avalanches were observed or reported.
Snowpack Summary
Several centimeters overnight with a few more through the day On Monday. A moderate to strong westerly flow insured windward slopes are being kept bare and lee aspects are receiving additional loading. Widespread wind slab conditions exist in in the alpine with similar but more sporadic conditions at treeline. These recently formed windslabs are sitting on a variety of old surface types including facets/suncrusts and in areas below treeline - surface hoar. None of these old surface layers are providing for a good bond between the old and new snow layers.
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.