Avalanche Forecast
Issued: Jan 10th, 2015 4:31PM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Persistent Slabs and Wind Slabs.
conrad janzen,
Avalanche Canada
Touchy buried surface hoar from Dec 18th, and widespread propagations on this layer, indicate the need to avoid avalanche terrain for a little while.
Summary
Weather Forecast
Moderate alpine temperatures between -5 and -10'C with light winds out of the NW and a mix of sun and cloud are expected for the next several days.
Snowpack Summary
Continuous widespread whumphing in Yoho indicates that the surface hoar on the rain crust problem down 45cm has not changed significantly since the last storm. Wide propagations indicate a good slab formation even below tree line. Areas of wind slab overlying weak facets near ridge tops and in exposed alpine areas are also prone to failure.
Avalanche Summary
Natural avalanche activity has tapered off but human triggering remains likely. A size 1.5 skier triggered avalanche occurred in the Wizard Chutes near tree line Jan 10th in the Sunshine area. Avalanche control at Lake Louise on Jan 9th resulted in a size 3 which initiated on the Dec 18th interface and then stepped down to facets near the ground.
Confidence
Problems
Persistent Slabs
The Dec 18 layer of surface hoar and crust is now buried 50-70 cm and primed for human triggering. Avoid any areas where avalanches can start at treeline and above.
- Whumpfing is direct evidence of a buried instability.
- Use conservative route selection, choose moderate angled and supported terrain with low consequence.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Wind Slabs
Recent strong winds have created wind slabs in open areas at tree line and above. If triggered these could easily step down to the Dec 18th layer and create a large avalanche.
- Avoid freshly wind loaded features.
Aspects: North, North East, East, South East.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Jan 11th, 2015 4:31PM
