Avalanche Forecast

Issued: Feb 14th, 2013 9:46AM

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

Avalanche Canada jlammers, Avalanche Canada

Weather models are disagreeing with expected snowfall totals for Friday. Danger ratings are based on the highest forecast snowfall amounts.

Summary

Confidence

Fair - Forecast snowfall amounts are uncertain on Friday

Weather Forecast

Friday: Moderate to heavy snowfall continuing overnight / Strong to extreme southwest winds / Freezing level at 800mSaturday: Light snowfall / Moderate to strong northwest winds / Freezing level at 300mSunday: Light snowfall / Light southwest winds / Freezing level at 100m

Avalanche Summary

A widespread natural avalanche cycle up to size 3 was reported in response to Tuesday's storm with the most activity appearing to occur close to Terrace. Explosives control in the region triggered lingering storm snow instabilities at treeline and above to size 2.5 on Wednesday.  Avalanche activity is expected to ramp-up again with weather forecast for Thursday evening/Friday..

Snowpack Summary

On Tuesday the region saw up to 80cm of new snow and an average of about 40cm. Strong winds have blown the new snow into wind slabs in exposed lee areas. The recent snow sits on above previous wind slabs on shady slopes in the alpine and at treeline, and a rain/sun crust at lower elevations/solar aspects, respectively.Deeper within the snowpack buried crusts exist, but are reported to have bonded well. I imagine that after the most recent avalanche cycle these will be difficult or near impossible to trigger in most areas, except with very large triggers such as a cornice fall.The mid and lower snowpack layers are generally well settled.

Problems

Storm Slabs

An icon showing Storm Slabs
Forecast rapid loading will create widespread slab avalanche conditions, especially in areas exposed to wind. Expect touchy wind slab/ storm slab conditions to prevail with the potential for large avalanches.
Avoid all avalanche terrain during periods of heavy loading from new snow or wind.>Stay off recent wind loaded areas until the slope has had a chance to stabilize.>Be aware of the potential for wide propagations due to the presence of hard windslabs.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

1 - 5

Valid until: Feb 15th, 2013 2:00PM