Weather Forecast
Synopsis: Precip amps up Tuesday night but should taper off by Wednesday mid-day. The trailing cold front brings freezing levels down slightly with no significant precipitation expected through the duration of the forecast period. Wednesday: Freezing Level: 1300m Precip: 5/10mm – 5/20cm. Wind: Mod, W/NWThursday: Freezing Level: 1000m Precip: Nil Wind: Strong, WFriday: Freezing Level: 1000m Precip: trace Wind: Mod, SW.
Avalanche Summary
Skiers continued to trigger avalanches to size 1.5 Monday. Most of these avalanches involve the new snow failing on the recently buried temperature crust on steep solar aspects. A few natural avalanches to size 2.5 were observed, likely occurring on this same interface.
Snowpack Summary
Recent snowfall amounts vary considerably with elevation due to fluctuating freezing levels. Some lee alpine areas may have accumulations over 50 cm. The new snow is sitting on a crust or moist snow depending on elevation. Dense new wind slabs are likely in exposed lee terrain at and above treeline. Most of the recent precipitation fell as rain or wet snow below 1700-1800 m. The upper snowpack at lower elevations has become isothermal from recent warm temperatures and rain. A frontal system passes over the region Tuesday evening which should bring snow above 1500m. Rain falling below treeline is unlikely to have much affect. Cornices are very large and could pop off with continued mild temperatures or during periods of sun.
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.