Avalanche Forecast
Regions: Purcells.
Check for pockets of wind slab around steep and high-consequence features.
Confidence
Moderate - Forecast snowfall amounts are uncertain.
Weather Forecast
Saturday night: Blustery with alpine flurries, up to 5 cm. Light west winds. Freezing level valley bottom, ridgetop low -10 C.
Sunday: Bands of convective moisture producing localized flurries up to 10 cm. Light southwest winds. Ridgetop high -3 C.
Monday: Overnight flurries bringing trace to 10 cm. Increasing east wind. Ridgetop high -4 C.
Tuesday: Cloudy with isolated flurries. Moderate northeast wind. Ridgetop high -10 C.
Avalanche Summary
A loose wet avalanche cycle from solar slopes began late Thursday afternoon. Explosives also triggered several size 1 wind slabs, all about 20 cm thick.
On Wednesday, a size 3 natural wind slab was observed on a northeast aspect at 2300 m.
Snowpack Summary
Wind has impacted 5-30 cm of recent snowfall. This covers a crust up to 2200 m and to mountain top on steep, solar slopes.
A thick rain crust with facets above from early December is buried around 100-200 cm deep. Large avalanches were naturally triggered on this layer during the last significant warming event in western terrain near the Bugaboos. With cold temperatures, avalanche activity on this layer is unlikely, however could easily wake up again with the next major input of moisture or heat.
Terrain and Travel
- Be careful with wind loaded pockets, especially near ridge crests and roll-overs.
- Wind slabs may be poorly bonded to the underlying crust.
- Pay attention to cornices and give them a wide berth when traveling on or below ridges.
Avalanche Problems
Wind Slabs
Any fresh snow will not bond well to the crust below. Check for reactive slabs below ridges and steep, convex slopes.
Aspects: North, North East, East, South East, North West.
Elevations: Alpine, Treeline.
Likelihood: Possible - Likely
Expected Size: 1 - 2