There were a lot of skier triggered avalanches yesterday! Hazard can increase rapidly during sunny breaks. Remember that other groups may be above or below you & regroup in safe spots. Avoid slopes exposed to large cornices above when the sun is out.
Weather Forecast
Unsettled weather, with generally mild temps, is expected through the weekend. Today will be cloudy, but strong solar radiation is expected during sunny breaks. Sunday is expected to be cloudy, with flurries bringing ~5cm. Monday will be mostly sunny, with alpine temps reaching 0'C. Below treeline, mild temps will prevent an overnight recovery.
Snowpack Summary
~50cm of snow in the past 5 days, combined sustained SW winds, is building a storm slab that is up to 1m deep on lee slopes. This slab overlies a crust, which provides a good sliding surface, on all aspects. Mild temps and periods of strong solar are making it reactive. Avalanches may step down to multiple crusts in the top meter.
Avalanche Summary
There were lots of skier triggered avalanches yesterday. A size 3 was accidentally triggered on the "Thorington", NE aspect ~2700m. It was ~1m deep and ran ~1km on the crust. Several size 2's were also triggered, they were up to 40cm deep running up to 500m. A lower elevations wet slabs were triggered. Luckily no-one was involved in any of them!
Confidence
Timing or intensity of solar radiation is uncertain
Problems
Storm Slabs
Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-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.
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.
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.