Avalanche Forecast

Issued: Feb 21st, 2013 9:46AM

The alpine rating is high, the treeline rating is considerable, and the below treeline rating is moderate. Known problems include Storm Slabs.

jlammers, Avalanche Canada

South Coast.

Summary

Confidence

Fair - Timing of incoming weather is uncertain for the entire period

Weather Forecast

Friday: Moderate to locally heavy snowfall with greatest amounts falling in the Coquihalla area / Strong to extreme southwest winds / Freezing level at 1100mSaturday: Trace amounts of new snow / Light northwest winds / Freezing level at surfaceSunday: Moderate snowfall / Moderate south winds / Freezing level at 1400m

Avalanche Summary

Fairly widespread sluffing in stepper terrain was reported from the Duffey area on Wednesday. I would expect a shift to significant storm slab instabilities with weather forecaster for Friday.

Snowpack Summary

Relatively light amounts of new snow have been redistributed into wind slabs in exposed areas at treeline and above and may overlie small surface hoar buried on February 20th.. On shaded slopes up to 25cm of snow may overlie surface hoar which was buried on February 12th. Most reports of this layer are coming from the Duffey Lake area. Recent snowpack tests have shown sudden planar fracture characteristics at this interface. On solar aspects and at lower elevations light accumulations overlie a melt freeze crust.The mid and lower snowpack pack layers are generally well settled.

Problems

Storm Slabs

Heavy snowfall and strong to extreme winds will create widespread storm/ wind slab conditions. Triggering avalanches will be highly likely, especially in wind-affected terrain.

Avoid all avalanche terrain during periods of heavy loading from new snow and wind.>Good day to make conservative terrain choices.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely - Very Likely

Expected Size

1 - 5

Valid until: Feb 22nd, 2013 2:00PM