Avalanche Forecast

Issued: Apr 22nd, 2014 9:02AM

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

Avalanche Canada esharp, Avalanche Canada

This forecast was build on limited field reports. If you head out into the mountains please tell us about the conditions you found. Send your observations to forecaster@avalanche.ca

Summary

Confidence

Poor - Due to the number of field observations

Weather Forecast

Synopsis: Southerly flow will continue to generate precipitation over the southern interior, Thursday will see drier conditions before an approaching trough off the coast forces a southerly flow pattern again on Friday.  Tonight and Wednesday:  Light precipitation continuing through the night, tapering off Wednesday afternoon - cm of snow at upper elevations. / Moderate westerly winds /  Freezing levels falling to 1500mThursday: Sunny with cloudy periods and chances of flurries / Light southerly winds / Freezing levels 2000mFriday: Flurries / light southeasterly winds / Freezing levels 2000m

Avalanche Summary

Small slabs have been recently triggered naturally and by skiers in areas where the upper snow is moist and sits above a crust. At lower elevations and on solar aspects small to large loose wet avalanche continue to be triggered on steep slopes. Cornices collapses have been reported during periods of daytime warming. Occasionally these heavy triggers have caused large deep slab avalanches on the slopes below.

Snowpack Summary

Snow line reached up to 2000m yesterday.A fresh crust on all but high elevation North aspects may now be buried by up to 15cm of new snow.  Below this 20 to 40cm of snow overlies older melt-freeze crusts from earlier in the month. Wind slabs can be found in lee features on N and E aspects in the Alpine.Several persistent weak layers exist in the highly variable snowpack of the South Columbia region:- The mid-March sun crust/surface hoar layer down 50-80cm and the early-March crust/facet/surface hoar layer down around 80-120cm seem to be inactive.- The mid-February crust/facet/surface hoar combo is typically down 150 - 200cm. Human triggered avalanches on this layer are unlikely. Larger triggers such as cornice fall, a smaller avalanche in motion or prolonged warming could wake this layer up, resulting in very large and destructive avalanche.

Problems

Wind Slabs

An icon showing Wind Slabs
Moderate winds have redistributed recent snow and wind slabs may be found in lee features on North aspects. Below 2200m these slabs may be sitting on a recent melt freeze crust.
Be careful with wind loaded pockets, especially near ridge crests and roll-overs.>The new snow will require several days to settle and stabilize.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Valid until: Apr 23rd, 2014 2:00PM