Avalanche Forecast
Issued: Mar 23rd, 2012 10:22AM
The alpine rating is Storm Slabs, Cornices and Deep Persistent Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
Poor - Timing or intensity of solar radiation is uncertain
Weather Forecast
Saturday will stay mostly dry, with sunshine and cloud. Winds should remain light. Freezing level should go to around 1800 m during the day. Sunday looks bright, sunny and warm, with freezing levels going up to around 2500 m. Very little overnight cooling is expected Sunday night as clouds move in overnight. Monday will stay warm, with freezing level around 2400 m and some good periods of sunshine.
Avalanche Summary
Several relatively small avalanches occurred in the storm snow on Thursday and into Friday. A fatal avalanche incident occurred in this region on Wednesday. We will post more details when they become available. On Monday and Tuesday avalanche activity was isolated to the recent storm snow. On Sunday a large avalanche occurred in the Lumberton snowmobile area in the East Kootenays: a snowmobiler accidentally triggered a very large (Size 3+) avalanche that resulted in a close call.
Snowpack Summary
10-20 cm new snow on Wednesday night followed a previous 20-30cm of new snow on Tuesday. This new snow has built storm slabs in many places and wind slabs in exposed leeward terrain. A sun crust that recently formed on southern aspects to around 1700 m and a spotty 2-6mm surface hoar on north and east aspects are now buried around 60-100cm. Below that, the more significant early February surface hoar is down 100-180cm. Avalanche activity has become more sporadic on this layer, but ongoing large events indicate it still has the ability to fail, despite how deeply it is buried. A melt-freeze crust, down 20-30cm, below 1800m provides some bridging to the layers below. Below the early February surface hoar layer, the snowpack is strong in most places. Cornices are very large and would act as a significant trigger for all the layers mentioned above if they drop.
Problems
Storm Slabs
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Cornices
Aspects: North, North East, East, South East.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Mar 24th, 2012 9:00AM