Avalanche Forecast
Issued: Jan 25th, 2018 4:26PM
The alpine rating is Storm Slabs and Persistent Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
Moderate - Due to the number of field observations
Weather Forecast
TONIGHT: Light flurries. Accumulation 1-5 cm. Ridge wind moderate, southeast. Temperature -7. Freezing level 200 m.FRIDAY: Cloudy, light flurries. Accumulation 2-7 cm. Ridge wind moderate, south. Temperature -7. Freezing level 200 m.SATURDAY: Mix of sun and cloud. Ridge wind moderate, east. Temperature -11. Freezing level valley bottom.SUNDAY: Snow. Accumulation 15-25cm. Ridge wind strong, southeast. Temperature -10. Freezing level 200 m. Alpine Inversion.
Avalanche Summary
Explosive control work on easterly aspects between 1100-1330 m, near Terrace on Thursday produced several storm slab avalanches up to Size 1.5 which failed on the most recently buried, mid-January crust layer.Wednesday, a naturally triggered cornice fall released a Size 2 storm slab avalanche on a steep, north aspect, and skier traffic in steep terrain produced only small, loose sloughs in the recent storm snow. On Tuesday there were reports of natural storm slab avalanches up to Size 2 failing on the mid-January interface and ski cut results produced storm slab avalanches to size 1.5 near ridge crest. In the Bear Pass area numerous natural wind slab failures from Size 1-2.5 were observed on wind-loaded northerly features as well as Size 1.5-2.5 naturals between 600-1200 m that ran on the mid-December crust layer. Monday, areas north of Stewart reported numerous natural loose storm snow avalanches on most aspects, and one skier remote Size 1.5 storm slab avalanche on a southerly aspect at 1400 m and is suspected to have failed on the mid-December interface following a large whumpf.
Snowpack Summary
Approximately 50-80 cm of recent storm snow covers a widespread crust as well as surface hoar in isolated areas at mid elevations that were buried mid-January. This surface hoar is more likely to exist in sheltered areas at treeline and below and has produced easy, sudden results in recent snowpack tests on northerly aspects between 1300-1450 m in areas north of Terrace.Professionals have also been monitoring a few mid-pack layers within the snowpack including a crust/ surface hoar layer that was buried early-January and now lies 60-100 cm below the surface, and a similar layer buried mid-December that now lies 80-120 cm below the surface. Both of these layers have been reactive in recent snowpack tests producing moderate to hard, sudden results and have produced recent large, natural avalanches particularly in northern areas of the region.The lower snowpack is generally strong, with the exception of areas around Stewart and further north where a basal crust and facets exist.
Problems
Storm Slabs
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Jan 26th, 2018 2:00PM