Avalanche Forecast

Issued: Mar 13th, 2014 9:23AM

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

Avalanche Canada rbuhler, Avalanche Canada

Summary

Confidence

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

Weather Forecast

The first frontal system will cross the south coast Thursday night and Friday morning. There is some uncertainty regarding the timing but the second system is expected on Saturday and should persist through Sunday.Thurs. Night/Friday: Snow 5-15cm, freezing level am: 1000m pm: 1500m, ridgetop wind 15-30 km/h SW-WSaturday: Moderate-heavy snowfall, freezing level am: 800m pm: 1400-1800m, ridgetop wind 20-40 km/h S-SWSunday: Light-moderate snowfall, freezing level am: 1400-1800m pm: 1000m, ridgetop wind 40-60 km/h SW

Avalanche Summary

Reports of natural avalanche activity up to size 2 on Wednesday from warming and solar radiation.

Snowpack Summary

The warm weather has resulted in good settlement of the snowpack and most of the layers are well bonded. There are still two weak layers that remain a concern but the problem is becoming isolated. However, the weight of the new storm snow may reactive these layers. The early March layer is down 60-100cm and the early Feb layer is down roughly 1.5m. It seems like these persistent weak layers are more of a concern in the northern parts of the region but may still pose a threat in the Coq and south. In the southern part of the region, widespread moist snow surfaces were reported to mountain top. Dry snow is still expected on northern aspects at treeline and above in the north of the region. A crust can be expected on most slopes and surface hoar has formed on sheltered slopes. In the north of the region, old wind slabs may still be a concern on N through E aspects from the last storm.

Problems

Storm Slabs

An icon showing Storm Slabs
New snow will sit on a sun crust and/or surface hoar. Expect new wind slab formation to be the primary problem for Friday. A widespread storm slab is expected as the storm progresses. Old wind slabs may still be a concern in the north of the region.
Avoid freshly wind loaded features.>The new snow will require several days to settle and stabilize.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

1 - 3

Deep Persistent Slabs

An icon showing Deep Persistent Slabs
There are a couple of persistent weak layers within the snowpack. While generally well bonded, the layer can still produce avalanches in isolated areas. Use extra caution in thin areas and on steep, unsupported features, especially on north aspects
Be aware of thin areas that may propogate to deeper instabilites.>Be aware of the potential for full depth avalanches due to deeply buried weak layers.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

3 - 6

Valid until: Mar 14th, 2014 2:00PM