Avalanche Forecast

Issued: Feb 10th, 2014 8:36AM

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

Avalanche Canada slemieux, Avalanche Canada

If snowfall amounts are greater than 10-15 cm, consider the danger rating to be higher than posted. If this is the case, stick to low angle and low consequence terrain.

Summary

Confidence

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

Weather Forecast

Synopsis: A strong Westerly offshore flow pattern is becoming established which is allowing a series of systems to come through for the remainder of the week. Tonight and Monday: A first frontal system approaches later Monday spreading light precipitation to the region. 5-10 cm of snow amount are forecasted with winds increasing to strong from the SW. Freezing levels are forecasted remain at the surface.Tuesday: Another, stronger system moves across the region spreading moderate amounts of precipitation with strong SW winds later during the day. Freezing levels are forecasted to rise to 1000 m briefly. Precipitation amounts are forecasted to be from 10 to 15 cm.Wednesday: Another system is forecasted to come through, expect moderate to heavy precipitation with similar freezing levels.

Avalanche Summary

A few small loose dry avalanches were observed today running out of steep terrain features. Expect more avalanche activity this week with the incoming weather.

Snowpack Summary

The first pulse of precipitation has started adding load to the snowpack. With around 10-15 cm of new snow and strong SW winds on the underlying weak surfaces, natural avalanche activity will be possible especially on alpine and treeline slopes lee of winds.  The new snow will fall on a variety of weak layers such as surface facets, on a new surface hoar layer in sheltered areas, or on 10-40 cm thick hard windslabs in the alpine. The bond of the new snow with these surfaces is expected to be poor. Don't let the lust for powder get in the way of safe decision making. It is good time to make conservative terrain choices and to reduce your exposure to avalanche terrain. At treeline, ~30 cm below the surface exist another surface hoar or suncrust layer that was buried late in January. The mid snowpack is strong and supportive. Deeper persistent layers have been dormant, however they could wake up again if the light to moderate precipitation amounts forecasted ends up having more punch.

Problems

Storm Slabs

An icon showing Storm Slabs
Storm slabs are developing with the ongoing and forecasted snowfall. Windslabs lee on SW-W winds in the alpine and at treeline and widespread loose avalanches are also a concern.
The recent snow will be hiding windslabs that were easily visible before the snow fell.>Choose conservative lines and watch for clues of instability.>Avoid freshly wind loaded features.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Likely

Expected Size

1 - 4

Valid until: Feb 11th, 2014 2:00PM