Regions
South Coast Inland.
Watch for new wind slabs and pockets of soft slabs at higher elevations.
Confidence
Moderate - Due to the number of field observations
Weather Forecast
Cold and clear for a few days. The next weather system arrives late Saturday. WEDNESDAY: Sunny. Light northeasterly winds (15-25Km/hr). Freezing level at valley bottom. Alpine high temperatures near -15 Celcius.THURSDAY: Sunny. Light southwesterly winds 10-20 Km/hr. Freezing level at valley bottom. Alpine high temperatures around -12 Celcius. FRIDAY: Sunny with a chance of flurries in the afternoon. Lightly southwesterly winds 10-20 Km/hr. Freezing level at valley bottom. Alpine high temperatures to -11 Celcius.
Avalanche Summary
On Saturday, skiers triggered a Size 2 wind slab near treeline on Zupjok peak (Coquihalla area). The culprit was northeasterly outflow winds loading southwest aspects. See the MIN post for more details:https://avalanche.ca/map/forecasts/south-coast-inland?panel=mountain-information-network-submissions%2Fd9620fad-38ad-4b09-adb2-e38941dbd6d4No new natural avalanches observed.
Snowpack Summary
Lingering soft slabs and wind slabs are the primary weaknesses of concern in the snowpack. 25-30cm of low density snow fell Sunday/Monday in the southern (Coquihalla) area, while northern sections received 7-15cms of new snow. Moderate southwesterly winds redistributed the new snow onto north (east) aspects forming reactive soft slabs. Winds shifted Tuesday to classic outflow (northerly) patterns with moderate winds at ridge top. This pattern has resulted in some 'reverse loading' of southerly slopes and creating wind slabs. Previous cold temperatures from last week and strong winds left our snow surface a mix of soft wind slabs, hard wind slabs, sastrugi, faceted snow, and even some surface hoar. These older wind slabs (on south - west aspects) remain a concern in our current snowpack and were triggered by skiers on Saturday (see link above).
Problems
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind 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.