Avalanche Forecast

Issued: Feb 15th, 2014 8:09AM

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

Avalanche Canada rbuhler, Avalanche Canada

Summary

Confidence

Fair - Timing, track, or intensity of incoming weather system is uncertain

Weather Forecast

A series of moist westerly systems from the Pacific continue to affect the interior regions.  A low pressure system will cross the interior Saturday night/early Sunday morning resulting in more precipitation with strong to extreme winds.  Sunday should be relatively dry before another system crosses the interior on Sunday night/Monday morning.  A third storm is expected for Tuesday.Sat. Night/Sunday: Snowfall 6-10cm easing in the morning, freezing level rising to around 1200m in the afternoon, ridgetop winds 50-70km/h SWMonday: Snowfall 8-12cm starting Sunday night, freezing level rising to around 1500m in the afternoon, ridgetop winds 50-70km/h SW easing in the afternoonTuesday: Snowfall 4-8cm, freezing level rising to around 1300m in the afternoon, ridgetop winds 30-50km/h SW

Avalanche Summary

A widespread natural avalanche cycle has been occurring across the forecast area over the last few days with natural and skier triggered avalanches up to size 3 being reported.

Snowpack Summary

Snowfall amounts have varied across the forecast region, but up to 100cm of storm snow is settling into a cohesive slab which is now typically 50-80cm thick. This slab is sitting on the weak Feb 9 interface which consists of multiple layers of surface hoar, faceted snow, and/or crusts from the past few weeks of cold clear weather. Reports indicate very easy snowpack tests results and widespread large destructive avalanche activity. Due to the persistent nature of these buried weaknesses, touchy conditions are likely to exist for some time.Strong ridge top winds have created wind slabs on leeward features at treeline and above. These wind slabs are the primary concern for the near future and strong-to-extreme forecast winds over the next few days are expected to add to this problem.For the most part, the mid and lower snowpack are strong and well consolidated. However, weak basal facets are likely to exist in some areas but triggering has now become unlikely.

Problems

Storm Slabs

An icon showing Storm Slabs
Large amounts of new snow is settling into a storm slab above the weak Feb.10th surface hoar/facet/crust interface.  Stiffer wind slabs also exist in leeward features in wind exposed areas.
Choose conservative lines and watch for clues of instability.>Use caution in lee areas in the alpine and at treeline. Recent wind loading has created wind slabs.>Avoid all avalanche terrain during periods of heavy loading from new snow, wind, or rain.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Likely - Very Likely

Expected Size

2 - 5

Valid until: Feb 16th, 2014 2:00PM