Avalanche Forecast
Issued: Mar 20th, 2012 10:21AM
The alpine rating is Storm Slabs, Wind Slabs and Deep Persistent Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
Fair - Timing, track, or intensity of incoming weather is uncertain
Weather Forecast
Wednesday: Convective snow showers. Moderate south-westerly winds, decreasing through the day. Freezing level around 700m.Thursday: Light snow. Light, south-easterly winds. Freezing level around 500m. Friday: Cloudy with flurries. Freezing level remaining near 500m.
Avalanche Summary
No new observations were reported on Monday. On Sunday, a size 3 loose avalanche failed naturally with solar warming on a south-east aspect in the Coquihalla area. A size 3 slab also failed on a north aspect, 1.5m deep and 100m wide. A few isolated avalanches were observed on Saturday in steep, rocky terrain. On Thursday, a natural loose moist avalanche cycle was observed in the Coquihalla region between 1400-1700m, with avalanches of size 2-3.5. A few slabs also released, with crowns of 50-60 cm. Explosives testing in the Duffey Lake area produced slab avalanches up to size 2.5 and skiers triggered very touchy storm slabs to size 1.5.
Snowpack Summary
Snow and wind created fresh wind slabs and storm slabs on Tuesday. Snow which fell last week is slowly settling, but variable storm snow weaknesses and buried crusts mean a deep storm slab release is still possible. Large cornices threaten slopes below. Crusts down around 60cm can be found on solar aspects in the Duffey Lake, Chilcotin, and Coquihalla areas. These exhibit moderate to hard, sudden results in snowpack tests.Deeper persistent weak layers are variable in distribution across the region. A crust/surface hoar/facet layer buried in early February, now down about 1.5m, is still is a key concern. It is especially prevalent on south-facing slopes above treeline, and all slopes below treeline. Although the likelihood of triggering this layer has decreased, the potential for surprisingly large avalanches remains.
Problems
Storm Slabs
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Wind Slabs
Aspects: North, North East, East, South East, South.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Deep Persistent Slabs
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Mar 21st, 2012 9:00AM