Avalanche Forecast

Issued: Feb 21st, 2016 8:23AM

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

Avalanche Canada bcorrigan, Avalanche Canada

Wind slabs may be touchy and reactive right now. Choose your objectives conservatively.

Summary

Confidence

Moderate - Due to the number and quality of field observations

Weather Forecast

The remnants of a Pacific frontal system will pass through the region later today bringing clouds and very light precipitation overnight and through Monday. No significant precipitation is expected. There should be a bit of a break Monday evening, then a weak system on Tuesday will bring clouds, but very little precipitation is forecast. A ridge of high pressure will rebuild over the province bringing clear skies and no precipitation through the remainder of the week. Freezing levels will rise to 1000 metres during the day, then drop to valley bottom overnight.

Avalanche Summary

Numerous natural, skier controlled and skier accidentals up to size 2 have been reported in the last 2 days on both sides of the divide. Early reports from today speak of a size 1.5 to 2 natural avalanche on a NE aspect at 1900m east of the divide.

Snowpack Summary

New snow and wind Friday night built wind slabs in lee terrain at treeline and in the alpine. A melt freeze crust which formed during the 2nd week of February has been reported 50 to 70cm from the surface in some areas. This crust layer has also  been reported with surface hoar in some places, mostly high and north facing. Rain and warm temperatures at lower elevations may have flushed out this weakness in some areas. West of the divide, a layer of buried surface hoar can be found between 70 and 90cm below the surface. Recent reports suggest this layer has become less of a concern.  As well the stormy weather has encouraged new cornice growth. These cornices may be huge and unsupported.

Problems

Wind Slabs

An icon showing Wind Slabs
Recent snow with wind has formed reactive wind slabs on the lee side of ridges at tree line and above.
Assess start zones carefully and use safe travel techniques.>Be careful with wind loaded pockets on steep slopes below ridge crests.>Stay off recent wind loaded areas until the slope has had a chance to stabilize.>

Aspects: North, North East, East, South East, South.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 3

Cornices

An icon showing Cornices
Cornices have grown large and fragile with the new snow and wind. Solar input can make them easily reactive.
Extra caution needed around cornices with current conditions.>Give cornices a wide berth when travelling on or below ridges.>Cornices become weak with daytime heating. >

Aspects: North, North East, East, South East.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 4

Valid until: Feb 22nd, 2016 2:00PM