Avalanche Forecast

Issued: Feb 18th, 2014 9:42AM

The alpine rating is high, the treeline rating is high, and the below treeline rating is considerable. Known problems include Storm Slabs.

Avalanche Canada ghelgeson, Avalanche Canada

You need to keep your objectives scaled back. The ticket right now is simple, well supported terrain that is free of overhead hazard. Don't let your lust for deep powder lure you into anything more committing.

Summary

Confidence

Fair - Forecast snowfall amounts are uncertain on Tuesday

Weather Forecast

Synopsis: Another pacific frontal system passes over the region Tuesday evening accompanied by strong SW winds. Expect isolated convective flurries to linger in the wake of the front Wednesday.Tuesday Night: Freezing Level: Valley Bottom; Precip: 5/6mm - 7/9 cm; Wind: Mod SW | Strong/Extreme SW at ridgetopWednesday: Freezing Level: 1000m; Precip: Trace; Wind: Light, West | Strong West at ridgetopThursday: Freezing Level: 1000m; Precip: 4/8mm - 6/12 cm; Wind: Strong, SW | Extreme SW at ridgetop.Friday: Freezing Level: Valley Bottom; Precip: Trace; Wind: Mod NW

Avalanche Summary

An ongoing avalanche cycle continues to produce natural avalanches to size 3. Skiers and sledders continue to easily trigger avalanches to size 2. In some cases, it's tough to discern what is releasing naturally and what is being remote triggered. This activity is taking place on all aspects and elevation bands.

Snowpack Summary

The never ending storm has produced 60 - 140 cm of total snowfall across the region which is settling into a cohesive slab that averages 45 - 80 cm in depth. This slab rests on a nasty persistent weak layer (Late Jan/Early Feb.) surface hoar/facet/crust combo that was formed during the month of cold clear weather. Large settlements / "whoomphs" have been reported at all elevations. Field observations continue to report easily triggered sudden planar failures on this interface in snowpack tests. Natural avalanches have been widespread and destructive. The persistent weak layer under all the storm snow is incredibly pervasive in the region. I expect touchy conditions to remain in place longer than we're normally accustomed to. Ongoing strong winds out of the SW and W have loaded lee aspects and damaged snow at all elevations, but the effect is most prevalent at and above treeline. More strong winds in the forecast are expected only to add to this problem.Weak basal facets exist in some areas, but triggering has now become unlikely. For the most part, the mid and lower snowpack are strong and well consolidated.

Problems

Storm Slabs

An icon showing Storm Slabs
A cohesive slab 40 - 80 cm in depth rests on a weak layer that remains very sensitive to human triggering.  This problem is widespread, even below treeline. Fresh wind slabs are forming in open terrain at and above treeline too.
Be aware of the potential for large, deep avalanches due to the presence of buried surface hoar.>Avoid all avalanche terrain during periods of heavy loading from new snow or wind>Use very conservative route selection, stick to simple well supported terrain that is low consequence and free of overhead hazard.>Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely - Very Likely

Expected Size

2 - 6

Valid until: Feb 19th, 2014 2:00PM