Some places saw phenomenal amounts of new snow on Tuesday: Give the snow time to settle and stick to conservative terrain. Limiting overhead hazard will be critical as well.
Confidence
Moderate - Due to the number of field observations
Weather Forecast
We're looking at unsettled weather with cool temperatures and isolated flurries throughout the forecast period.WEDNESDAY: A mix of sun and cloud and isolated flurries. Moderate north/west winds 20-45 Km/hr. Freezing level to 1400 metres with alpine high temperatures around -6. THURSDAY: Sunny with cloudy periods and isolated flurries. Winds becoming light westerly. Freezing level to 700 metres with alpine high temperatures of -8.FRIDAY: A mix of sun and cloud with isolated flurries. Light north / west winds. Freezing level 500 metres with alpine high temperatures around -9.
Avalanche Summary
We haven't had any observations from the field but a widespread natural avalanche cycle is expected to have happened on Tuesday with all the storm snow.
Snowpack Summary
There were some incredible amounts of (heavy) new snow on Tuesday, ranging from 18 to 46 cm. Winds have been moderate to strong from the south / west. Last week saw a wind-affected 15-30 cm of new snow, which sits on a variety of snow surfaces: older storm snow or wind slabs up high, or sun crusts at lower elevations and on south aspects. Surface hoar layers have been reported on shaded aspects at higher elevations and might now be found at approximately 50 and 80 cm below the surface. Persistent weak layers from early January and mid-December are still being reported by local operators. They are generally considered dormant, but could wake up with a surface avalanche stepping down, a large cornice fall, or a human trigger in a shallow or variable-depth snowpack area. These layers consist of sun crust, surface hoar and/or facets.
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.