Avalanche Forecast

Issued: Mar 30th, 2014 9:55AM

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

ghelgeson, Avalanche Canada

Northwest Inland.

Summary

Confidence

Poor - Due to the number of field observations

Weather Forecast

Synopsis: A ridge of high pressure over the NWT continues to advance south. Looks like continued cool and dry conditions for the NW for the forecast period. The models show an organized system that approaches the north coast Wednesday/Thursday, check back tomorrow for more details. Monday: Freezing Level: 800 - 1300m; Precipitation: Nil; Wind: Treeline: Light, NW | Ridgetop: Light, NWTuesday: Freezing Level: 600 - 1300m Precipitation: Nil; Wind: Treeline: Light, SW | Ridgetop: Moderate, WWednesday: Freezing Level: 400m - 1300m; Precipitation: Trace; Wind: Treeline: Light, S | Ridgetop: Moderate, SW

Avalanche Summary

No new activity to report from Saturday.On Friday a skier remote triggered a size 1 wind slab on a southwest facing feature at 1500m. Loose snow avalanches to size 2 were running in the recent storm snow on both SW and NE facing slopes Thursday. One fresh wind slab on a NE facing feature at 1700m was also reported. We received a report of a skier triggered avalanche in the Kispiox range that occurred on Wednesday. The size 2 avalanche caught and carried a skier on an alpine feature, thankfully the skier walked away from the incident. Sounds like it ran on the March crust/facet/surface hoar interface.

Snowpack Summary

The recent storm snow (40-50 cm) has been transported into pockets of wind slab by moderate Southwest winds in the South of the region and by Easterly winds in the North of the region. The storm slab is sitting on the March persistent weak layer of crusts/facets/surface hoar that is widespread across the region. A late January/early February crust/facet/surface hoar combo is still showing up in snowpack tests with moderate to hard shear test results. This layer is expected to be with us for a long time, and a slide triggered on this layer could be very large and destructive.

Problems

Wind Slabs

Strong winds have created isolated pencil hard wind slabs 20 - 50 cm in depth at and above treeline. Where new snow is available for transport, soft slabs may be found too.

Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.>Watch for areas of hard wind slab on alpine features.>Use ridges or ribs to avoid pockets of wind loaded snow.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 4

Deep Persistent Slabs

At this point the deep persistent weak layers would likely require a specific trigger like cornice fall, a surface avalanche in motion, or a rider finding the sweet spot, to be activated.

Avoid convexities or areas with a thin or variable snowpack.>Be aware of the potential for large, deep avalanches due to the presence of buried weak layers.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Unlikely - Possible

Expected Size

3 - 6

Valid until: Mar 31st, 2014 2:00PM