Avalanche Forecast
Issued: Dec 7th, 2013 8:30AM
The alpine rating is Wind Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
Fair - Due to the number of field observations
Weather Forecast
Arctic air will slowly dissipate and alpine temperatures are forecast to climb towards -10 by Tuesday. Freezing level will remain at valley bottom. A Pacific frontal system is forecast to arrive on the coast Wed. or Thurs. and move into the interior bringing milder temperatures and precipitation. Timing and amount of moisture is uncertain.
Avalanche Summary
No reports of recent avalanche activity. Wind slabs on lee slopes are the major concern at this time.
Snowpack Summary
Snowpack depths vary greatly across the south coast inland area. Reports from the Cascades show 160cm @ 2000 metres, but the Duffey lake has only 54 cm at 1890 m.Arctic outflow N winds continue to scour north slopes and deposit wind slabs on S-SW slopes at tree line and above . Surface hoar is growing in protected locations near tree line and reports on Friday indicate the storm snow is faceting down to 30 cm from the surface.Terrain below tree line is mostly below threshold for avalanche activity and solid. A few crusts with faceting may be found near the base of the snowpack, especially at higher higher elevations. No observations of avalanches on these crust/facet layers have been reported up to this time, but they are worth keeping an eye on.
Problems
Wind Slabs
Wind slabs at tree line and above are the prime concern at this time with the possibility of initiating a larger more destructive avalanche in some select areas. There are crusts and facets buried deeper in the snowpack than we should not forget.
Avoid lee and cross-loaded terrain near ridge crests.>Be cautious as you transition into wind affected terrain.>Dig down to find and test weak layers before committing to a line.>Forecasters are operating with alot of uncertainty at this time.>
Aspects: North, North East, East, South East, South, South West.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Dec 8th, 2013 2:00PM