Avalanche Forecast
Issued: Jan 16th, 2015 8:08AM
The alpine rating is Wind Slabs, Persistent Slabs and Loose Dry.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
Fair - Timing, track, or intensity of incoming weather system is uncertain on Sunday
Weather Forecast
A weak ridge of high pressure will keep the interior dry for Friday night and Saturday morning. Light flurries are expected Saturday afternoon with moderate SW alpine winds. Freezing levels should be at around 1000m. On Sunday, another frontal system will cross the interior bringing 10-20mm of precipitation and moderate-strong SW alpine winds. Freezing levels may reach around 1500m. Lingering flurries are expected for Monday a ridge of high pressure begins to build over the interior.
Avalanche Summary
On Thursday, a natural cornice fall triggered a size 1 persistent slab which released on the mid-Dec layer. On Wednesday, explosives triggered a cornice but the cornice did not trigger a slab. On Tuesday, a natural size 2.5 persistent slab was reported. This released on the mid-Dec weak layer. Some natural avalanche activity is possible on Saturday in specific areas including fast sluffing from steep terrain and wind slabs in leeward alpine features. Small avalanches have the potential to step down and trigger a persistent slab which would greatly increase the consequences. Skier triggering is likely in wind loaded areas and steep terrain, and remains possible for persistent slabs where the tricky mid-December layer is still intact.
Snowpack Summary
The new snow has buried widespread 10-20mm surface hoar, a sun crust on steep sun exposed slopes, and/or wind affected surfaces in the alpine. The problematic mid-December surface hoar/crust layer is typically down 80-120cm below the new snow and remains sensitive to human triggering is some areas. The reactivity of this persistent weak layer appears to be quite variable but still has the potential for large, destructive avalanches in some areas. The layer appears to be the most reactive at and below treeline.
Problems
Wind Slabs
Aspects: North, North East, East, South East, South, South West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Loose Dry
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Jan 17th, 2015 2:00PM