Diligence may be required to maintain conservative decisions when seeking decent riding conditions over the weekend.
Confidence
Fair - Due to the number of field observations
Weather Forecast
Only trace amounts of snow are expected throughout the forecast period. Expect generally overcast skies with occasional sunny breaks on Sunday and Monday with increased cloud on Tuesday. Freezing levels are expected to remain at valley bottom, while ridge top winds will remain generally light.
Avalanche Summary
Recent reports include numerous small natural loose snow and thin storm slab avalanches on steep sun-exposed slopes, as well as a small skier controlled slabs on a north aspect. One Size 2 80 cm deep persistent slab avalanche was accidentally triggered by a goat on a steep south aspect in the alpine... not sure if he got out...
Snowpack Summary
Recent storm snow has been redistributed into thick wind slab on lee slopes at treeline and alpine elevations from moderate to strong westerly winds. Warm alpine temperatures have moistened the surface snow with a breakable surface crust forming on steep sun-exposed slopes. The mid-December surface hoar/crust persistent weak layer down 50-90 cm is still producing easy to moderate sudden planar test results at treeline elevations and below. Recent reports of whumpfing and the general nature of this weakness suggest it is susceptible to remote triggering and widespread propagation.
Problems
Persistent Slabs
Persistent Slab avalanches are the release of a cohesive layer of snow (a slab) in the middle to upper snowpack, when the bond to an underlying persistent weak layer breaks. Persistent layers include: surface hoar, depth hoar, near-surface facets, or faceted snow. Persistent weak layers can continue to produce avalanches for days, weeks or even months, making them especially dangerous and tricky. As additional snow and wind events build a thicker slab on top of the persistent weak layer, this avalanche problem may develop into a Deep Persistent Slab.
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.