Avalanche Forecast

Issued: Feb 17th, 2013 8:19AM

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

Avalanche Canada ghelgeson, Avalanche Canada

Summary

Confidence

Fair - Due to variable snowpack conditions

Weather Forecast

Monday:  Freezing Level: 500m Wind: Mod S/SW, No significant precip.Tuesday: Freezing Level: 500m rising to 750m, Wind: Light W, No significant precip.Wednesday: Freezing Level: 500m Wind: SW, initially moderate increasing to strong by sundown.  10cm of snow expected.

Avalanche Summary

Improved visibility on Saturday revealed the extent of a large natural avalanche cycle in the North.  The big winds and large snowfall drove a cycle to size 3.5. Observations in the southern half of the region were much smaller with cornice failures resulting in size 2 avalanches. The sun is really gaining strength as we get closer to the Spring Equinox which is driving ongoing point releases on solar aspects.

Snowpack Summary

The latest storm continued through Friday evening which brought 70cm of relatively warm snow to the Northern half of the region.  Southern storm totals average around 20cm.  The storm was accompanied by moderate winds that were initially out of the SW switching to NW during the later half of the storm.  The winds left a mix of wind damaged snow in both the alpine and treeline elevation bands. Slab properties vary from upside down soft slab to stiff and deep wind slab.  With all the new snow and wind I imagine that there is quite a bit of cornice development in the region too.The mid and lower snowpack layers are generally well settled.

Problems

Wind Slabs

An icon showing Wind Slabs
Winds out of the NW, W and SW created both soft slabs and deep stiff hard slabs which are drainage dependent, but are generally shallower and softer in the southern half of the region.
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.>Extra caution needed around cornices with current conditions.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 6

Valid until: Feb 18th, 2013 2:00PM