Avalanche Forecast

Issued: Nov 27th, 2015 8:24AM

The alpine rating is below threshold, the treeline rating is below threshold, and the below treeline rating is below threshold. Known problems include Loose Wet, Wind Slabs and Deep Persistent Slabs.

bcorrigan, Avalanche Canada

Cariboos.

Use caution as the temperatures rise in the next few days. Big shout-out to riders who are sending their observations to the MIN !Join the club, and share your observations to make riding safer for everyone !

Summary

Confidence

Fair - Due to the number and quality of field observations

Weather Forecast

An arctic high continues to dominate the weather pattern over western Canada and is not forecast to move out of the area until Tuesday or Wednesday next week. In the meantime, an above-freezing layer (AFL) of air will pass through the region between 1500 and 3000m bringing temperatures in that elevation band to as high as +5°c., especially on solar aspects. Arctic air pooling in the valley bottoms will keep the temperatures well below freezing until the next storm system flushes out the cold air.

Avalanche Summary

Some surface sluffing of storm snow noted on S aspects in steep terrain, but the wind slabs left over from the most recent wind events are still lurking out there. Exercise caution on steep solar aspects during periods of intense warming.

Snowpack Summary

The snowpack has been described by local observers as "extremely variable", with wind effect in all open alpine areas from the Northerly winds after the last storm. Surface hoar is widespread and has been observed to 4mm in sheltered locations, while windward slopes have been scoured down to bare rock in many parts of the region. Cold arctic air and temps down to -20 in some areas are promoting surface facetting. Previously discussed surface hoar, crust, and facet layers appear to be non-reactive with the exception of the surface hoar buried on Nov. 24th. Some reported sluffing in steep terrain suspected on this layer where it still exists. The above-freezing-layer now moving through the region could dramatically alter the snowpack.

Problems

Loose Wet

An above freezing layer (AFL) combined with strong solar radiation may create conditions for loose wet avalanches on solar aspects. Use caution riding on or under big steep slopes that face south!

Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.>

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

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 4

Wind Slabs

Wind slabs on south slopes that are left from the last strong northerly winds may still be waiting for a trigger. Use caution in wind affected areas

Be cautious as you transition into wind affected terrain.>Avoid travelling in areas that have been reverse loaded by winds.>Avoid freshly wind loaded features.>

Aspects: North, North East, East.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 3

Deep Persistent Slabs

Be aware of thin areas that may propogate to deeper instabilites.>Now is a good time to dig a snow profile (or two) and figure out how the snowpack changes with aspect and elevation.>Avoid shallow snowpack areas where triggering is more likely.>

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

Elevations: Alpine.

Likelihood

Unlikely

Expected Size

1 - 4

Valid until: Nov 28th, 2015 2:00PM