Avalanche Forecast
Issued: Apr 3rd, 2017 4:01PM
The alpine rating is Storm Slabs, Persistent Slabs and Loose Wet.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
Moderate - Timing or intensity of solar radiation is uncertain on Tuesday
Weather Forecast
Overnight: High overcast with light winds and freezing down to valley bottoms. Tuesday: Mix of sun and cloud with moderate southwest winds and daytime freezing up to 1400 metres. Wednesday: Overcast with afternoon flurries and moderate southwest winds. Daytime freezing up 1800 metres. Thursday: A few cm of new snow by morning. Winds becoming light and daytime freezing around 1800 metres.
Avalanche Summary
Natural storm slab avalanches up to size 3.0 were reported on Sunday from both the Monashees and the Selkirks. Natural and explosives controlled cornice falls released up to size 2.5 on their own, and up to size 3.0 where they pulled a slab on the slope below. A solid overnight re-freeze down to valley bottoms is forecast, setting up a spring melt-freeze cycle over the next few days.
Snowpack Summary
10-20 cm of recent snow now overlies a crust below about 2200 metres on (higher on solar aspects) and moist snow below about 1700 metres. Below the new snow interface, storms over the past week brought 40-60 of snow to the region. Several other crusts as well as moist snow are likely to exist within this storm snow, mainly at lower elevations and on solar aspects. Moderate to strong southwest winds during and since the storm formed wind slabs on leeward slopes as well as fragile cornices along ridgelines. 90-130 cm of accumulated snow now overlies a more widespread rain crust below 2000 m and sun crust on solar aspects at higher elevations. At higher elevations, the February weak layers are down 160-200 cm and the deep mid-December facet layer and November rain crust both still linger near the bottom of the snowpack. These layers were active during a storm in mid-March and produced some very large avalanches. Occasional deep releases were also reported in late March and these deeply buried weaknesses remain a serious concern as solar radiation and warming temperatures begin to penetrate the snowpack at increasingly higher elevations.
Problems
Storm Slabs
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Loose Wet
Aspects: North, North East, East, South East.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Apr 4th, 2017 2:00PM