Once again we are expecting an upslope storm to bring some snow. It will start tomorrow and carry on into Thursday. Remember that upslope storms have a tendency to reverse load slopes.
Confidence
Moderate - Intensity of incoming weather systems is uncertain
Weather Forecast
Flurries with light winds overnight. We are expecting a stronger and more unsettled system to arrive by tomorrow afternoon bringing almost 10cm of new snow. SE winds will be a bit stronger as this storm plays out. On average 20 km/hr with gusts up to 45 in exposed areas. The alpine high will reach -4. Freezing level 2000m.
Avalanche Summary
Only small loose dry avalanches were noted today in steep alpine terrain.
Snowpack Summary
No significant new snow last night, only a light dusting in the southern part of the forecast region. Cold dry snow still exists in the high alpine and northern aspects. A significant melt freeze crust is on all aspects up to 2300m, and higher on solar aspects. The cloud cover and cooler temps today helped keep the crust frozen and supportive everywhere except for the valley bottoms. Moist snow by mid afternoon. Tests today revealed no significant shears at treeline elevations, however expect to still find the Dec facets near the bottom of the snow and potentially reactive to human triggering in thin areas.
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.