With more snow in the forecast, expect storm slabs.
Weather Forecast
The next wave of warm and wet weather is expected to arrive by Saturday morning with freezing levels forecasted to rise to 2500m on Sunday.Saturday: Snow, accumulation 20-30 cm. Moderate to strong south wind. Alpine temperature -1. Freezing level 1500 m.Sunday: Heavy snow and rain below 2000 m, accumulation 30-40 cm. Strong south wind. Alpine temperature 2, Freezing level 2500 m.Monday: Flurries, accumulation 5-10 cm. Moderate southwest wind. Alpine temperature -5. Freezing level 1000 m.
Avalanche Summary
Wednesday's rain to mountain tops produced numerous, small to very large natural, loose, wet avalanches as rain drenched all elevations. In some areas these avalanches were associated with debris flows and several washouts along FSR roads and trails have been reported. Avalanche activity has since subsided with a return to cooler temperatures and lower freezing levels but will increase again as the new snow and wind build storm slabs at alpine and treeline elevations.
Snowpack Summary
Approximatley 20-30 cm of new snow overlies the November 23 crust This 5-10 cm thick crust can be found on all aspects above 1400 m and overlies a saturated upper pack. Below treeline the snowpack consists of wet snow from top to bottom. In high alpine and glaciated terrain the November 9th layer of weak sugary crystals above a crust near the base of the snowpack is now buried 150 - 240 cm deep.
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.
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.