Cooler temps with cloud cover will help the snowpack recover some strength on Saturday. If the sun does comes out, expect the avalanche danger to rapidly increase, especially on solar aspects.
Weather Forecast
More cloudy and cooler temperatures are forecast for Saturday with even a chance of some rain. If the forecast comes true, we can expect a good freeze overnight and then clouds moving in around 6am with a generally cloudy day forecast. This will allow the snowpack to recover overnight and remain cool during the day. If the sun comes out though, we can expect avalanche danger to return to high on these solar aspects quickly.
Avalanche Summary
Loose wet and wet slab avalanches up to sz 2 were common on Friday.
Snowpack Summary
Moist snow was found up to the summits of regional peaks on all but true north aspects in alpine areas by 10:30 am on Friday. Treeline and below unskied areas were also becoming isothermal and unsupportive by mid day. Loose wet slides are failing and pulling out slabs in some areas that are overlying the weak basal facets that have been an issue all season. Where they are not pulling out slides they are gouging out the facets and running far. This weeks heat has been a shock to the snowpack and in the long term conditions will improve with cooler temperatures but until then, there is a wet upper snow pack overlying weak basal facets.
Problems
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.
Loose Wet
Loose Wet avalanches are the release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry Avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.