Avalanche Forecast

Issued: Dec 16th, 2013 8:20AM

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

Avalanche Canada bcorrigan, Avalanche Canada

Forecasters are working with little field observation data at this time. If you have been out in the mountains, please send us you information and observations. Send to:forecaster@avalanche.ca

Summary

Confidence

Fair - Intensity of incoming weather systems is uncertain

Weather Forecast

Tuesday: Another storm makes landfall on the northwest coast, the inland northwest could see 10 to 20 cm of new snow at upper elevations with strong southwest winds at ridge top.Wednesday: Cool arctic air moves into the region bringing freezing levels down to valley bottoms.Thursday:  Cold arctic air remains in the region as the arctic front moves south.

Avalanche Summary

No new avalanches have been reported. This likely speaks more to the lack of observations than actual conditions. Strong winds, new snow, and warm temperatures are expected to increase the sensitivity to triggering by skiers and sledders.

Snowpack Summary

There is wide variation in snow depths across the region. Areas in the Southwest (Howson range) are likely similar to the Northwest Coastal region. Around Smithers, reports suggest snow depths of 70-90cm at treeline.The northern portion of the region received a bit more snow (upwards of 20cm) than the south (Smithers area) which received 10 to 20 cm overnight. In areas that received significant new snow amounts, the snow is settling into a storm slab, accelerated by the recent warm temperatures. Very strong winds have transported snow into layes of cohesive, wind pressed snow. Cold temperatures at the beginning of December created facetted snow and surface hoar above old wind and melt-freeze crusts. The new warmer storm snow is not expected to bond well to these old buried layers which range from 20-40cm below the surface. The mid and lower snowpack is fundamentally weak, and is composed of facets, depth hoar and an early season crust near the base of the snowpack.If you have been out, we would love to hear about it. Please send your observations to forecaster@avalanche.ca.

Problems

Storm Slabs

An icon showing Storm Slabs
The concerns at this time are wind loaded areas at tree line and above.  The more dense wind loaded snow may not be well bonded to the facetted snow underneath, and may be highly reactive to skier or sled loading.
Be cautious as you transition into wind affected terrain.>Minimize exposure during periods of heavy loading from new snow, wind.>The new snow will require several days to settle and stabilize.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

2 - 3

Valid until: Dec 17th, 2013 2:00PM