Avalanche Forecast

Issued: Jan 1st, 2015 8:56AM

The alpine rating is considerable, the treeline rating is considerable, and the below treeline rating is moderate. Known problems include Persistent Slabs and Wind Slabs.

Avalanche Canada swerner, Avalanche Canada

Recent snowpack and avalanche observations from the Rossland Range indicate that the Danger Rating below treeline is CONSIDERABLE. The Special Public Avalanche Warning is extended through the weekend.

Summary

Confidence

Fair - Intensity of incoming weather systems is uncertain

Weather Forecast

Increasing cloud, moderate west winds and some light flurries are expected overnight Thursday. On Friday, cloudy skies with snow amounts near 5 cm. Alpine temperatures near -10. A brief lull in the pattern for Saturday as a second Pacific low deepens off the coast. This low could bring moderate amounts of snow to the Interior Sunday afternoon and overnight into Monday, however; confidence is poor with timing and precipitation amounts due to model discrepancies.

Avalanche Summary

In the Rossland Range, reports indicate that the mid-December crust/ surface hoar/ facet layer seems to be very touchy and numerous naturals and human triggered avalanche activity has occurred over the past few days. Elevations ranging from 1900-2300 m seem to be hot spots, and conservative terrain selection is critical even in the trees where you tend to let your guard down. Reports from other parts of the region indicate a skier remote size 2 (15 m away) on a west aspect at 2100 m and a skier triggered size 1 on a west aspect at 2170 m, both of these failing on the mid-December surface hoar. In locations that have seen more wind, this layer sensitivity is touchy to light loads, like YOU.

Snowpack Summary

Snow surfaces are variable with northerly, wind exposed aspects showing firm wind press or scoured exposed crust, and sheltered locations have up to 35 cm of light, low density, faceted snow above a recently formed surface hoar. Strong northerly winds have transported the new snow onto southerly aspects creating stiff and reactive wind slabs. Up to 80 cm below the surface, a touchy weak layer of surface hoar sitting on a thick rain crust exists. This widespread persistent weak layer comprising of surface hoar/ facets and a hard rain crust was buried mid-December and continues to produce whumpfing and sudden planar characteristics in snowpack tests. Although high elevation slopes may not have the rain crust, they are still reported to have touchy buried surface hoar. At the base of the snowpack, a crust/facet combo appears to have gone dormant for the time being.

Problems

Persistent Slabs

An icon showing Persistent Slabs
A persistent weak layer, buried 30-80 cm below the surface continues to be a concern and skier/ rider triggering is likely.
Use conservative route selection at all elevations, stick to moderate angled terrain with low consequence and be aware of what is above you at all times as remote triggering is a concern.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely

Expected Size

2 - 5

Wind Slabs

An icon showing Wind Slabs
Recent strong northerly winds has transported new snow into pockets of stiff and reactive wind slab. Due to the reverse loading pattern, wind slabs may be triggered in unsuspecting locations.
Avoid travelling in areas that have been reverse loaded by winds.>Whumpfing, shooting cracks and recent avalanches are all strong inicators of unstable snowpack.>

Aspects: North, North East, East.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 3

Valid until: Jan 2nd, 2015 2:00PM