Avalanche Forecast
Issued: Dec 29th, 2013 8:32AM
The alpine rating is Wind Slabs and Persistent Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
Poor - Wind effect is extremely variable
Weather Forecast
Synopsis: NW flow continues to dominate the pattern. A few cms may make it into the region, but no significant accumulations are expected. The big player over the next few days will be the wind. 2000m wind forecasts are provided below, 3000m winds are roughly 1.5x greater.Monday: Freezing Level: Valley Bottom; Precip: Nil Wind: Mod NW/WTuesday: Freezing Level: Valley Bottom; Precip: 1/2mm 2/5cm Wind: Mod W switching to Strong NW near sundown.Wednesday: Freezing Level: Valley Bottom; Precip: Nil; Wind: Initially Mod NW switching to Light SW by Wednesday evening.
Avalanche Summary
On Christmas Eve a backcountry skier triggered a size 2 slab avalanche on an alpine slope in the Harvey Pass area. The slab was reportedly 70cm deep and 150m wide and was thought to have slid on the late-November crust/facet interface. There were no reported injuries with the avalanche.No other avalanches have been reported.
Snowpack Summary
There appears to be a lot of snowpack variability across the region. Snowpack depths at treeline seem to vary from 60 - 130 cm with high variability in wind-exposed areas. Winds have been strong out of the SW on Sunday at all wind stations. With 10 - 15 cm available for transport I expect wind slabs to be touchy on Monday. In the mid pack is the late-November/early-December interface which is made up of surface hoar, a crust, and/or facets. This layer is typically down 30-70cm and has reached the tipping point for rider triggering in a few areas including the Harvey Pass area. Check out this video of a recent snowpack test on this layer. We're probably getting close to this layers tipping point in wind loaded terrain at treeline in much of the region.Â
Problems
Wind Slabs
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Dec 30th, 2013 2:00PM