Avalanche Forecast
Regions: South Rockies.
Confidence
Fair - Forecast snowfall amounts are uncertain
Weather Forecast
Wednesday: Cloudy with a few snowflakes. Cold (around -18C). Moderate to strong westerly winds. Freezing level valley floor.Thursday: Light snow possible at times. Remaining cold. Friday: The next frontal system is due to hit the region late in the day, bringing moderate-heavy snow, rising temperatures and gusty winds. Freezing level climbing near 1500m by the evening. The timing of this system is uncertain.
Avalanche Summary
Natural avalanche activity was likely to have peaked during the most rapid loading on Tuesday. Fast-running loose snow avalanches were reported. Observations have been limited by poor travel conditions.
Snowpack Summary
Intense snowfall which started on Monday night and persisted through Tuesday, with rates of 5-7cm/hr observed, was centred on the Lizard Range. In the South Rockies region, the Flathead and southern Elk Valley received the most snow (around 30cm), with lesser amounts further east and north. The snow was exceptionally light and dry and has shown little slab properties, but is running easily as fast-moving sluffs. It came with no wind at Castle Mountain and mainly light winds in other parts of the region. Below the storm snow, older wind slabs appear to be well bonded. Expect new wind slabs to develop if the wind rises.Besides new storm/wind-related concerns, the main layer we're watching in the region is a surface hoar layer buried in early December. It's down about 1m in the Flathead and recently exhibited hard, sudden planar/full propagation results, meaning that's it was stubborn to trigger but could create a large avalanche. Facets sandwiched between two firm layers in the top metre of the snowpack are being monitored in the south-east.
Avalanche Problems
Loose Dry
Aspects: All aspects.
Elevations: All elevations.
Likelihood: Likely - Very Likely
Expected Size: 1 - 4
Wind Slabs
Aspects: North, North East, East, South East.
Elevations: Alpine, Treeline.
Likelihood: Likely - Very Likely
Expected Size: 1 - 4
Persistent Slabs
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood: Unlikely - Possible
Expected Size: 1 - 6