Strong winds are creating new windslabs in Alpine areas. Pay close attention to the input of solar radiation as you travel in relation to overhead terrain. Freezing levels are forecast to be valley bottom overnight.
Confidence
Moderate - Timing or intensity of solar radiation is uncertain on Saturday
Weather Forecast
No new snow is forecast over the next 24hrs and temperatures are still forecast to remain cool. Winds will continue to be strong out of the SW which will help to keep the snowpack cooler but when the sun comes out, stability will quickly deteriorate on solar aspects, especially steeper or rocky terrain.
Avalanche Summary
A few loose wet slides were observed that had likely come out after the forecasting day on Thursday. Otherwise, there were no new avalanches on friday.
Snowpack Summary
Only a skiff of new snow over the past 24hrs. Of note the winds were howling (aka strong) out of the SW at higher elevations. Widespread snow transport was observed in alpine terrain and as a result new windslabs were forming at higher elevations on lee aspects. Temperatures remained somewhat cool but we did see some moist snow later in the afternoon on solar aspects. On Thursday the warm temps had moist snow up to 2400m on all aspects. As a result, surface crusts should be expected in most areas making the skiing challenging. Dry powder snow is pretty much only likely in high alpine areas on North aspects. On solar aspects, crusts are bing observed up to 2700m.
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.