Avalanche Forecast

Issued: Jan 1st, 2014 8:30AM

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

rbuhler, Avalanche Canada

Northwest Coastal.

Summary

Confidence

Fair - Intensity of incoming weather systems is uncertain on Thursday

Weather Forecast

The storm system will ease on Thursday. On Friday a ridge of high pressure will build and dry conditions are expected on Saturday.Thursday: Precipitation in the morning (2-5cm) ending by the afternoon, freezing levels 300-500m, light to moderate W-NW ridgetop windsFriday/Saturday: A mix of sun and cloud, dry conditions, treeline temperatures -10 to -15C, light to moderate NW ridgetop winds

Avalanche Summary

No recent natural avalanches have been reported.

Snowpack Summary

Southern Sections: 40-50cm of new snow has fallen in the last 4 days. The recent storm snow is likely "upside down" feeling, with heavier snow on top due to warming at the tail end of the system. Winds were also very strong from the SW most likely creating fresh wind slabs in exposed lee terrain at all elevations. Freezing levels climbed to near 1500 m resulting in moist snow or rain below treeline. Much of the low elevation snowpack has been washed away by recent rain.Northern Sections: Weaknesses may still exist within the recent storm snow. Fresh dense wind slabs are likely in exposed lee terrain and cross-loaded features at all elevations. A recently buried surface hoar layer is now down around 80 cm and is likely primed for rider triggering. A facet/crust layer exists near the base of the snowpack, primarily on higher NW through E facing slopes. Triggering this layer may be unlikely, but if triggered the resulting avalanche would be very large and dangerous.

Problems

Storm Slabs

Storm slabs and wind slabs continue to build and may release naturally with more load or from the weight of a rider. Watch for touchy wind slabs on exposed north through southeast facing slopes and cross-loaded features in the alpine and treeline.

Avoid all avalanche terrain during periods of heavy loading from new snow, wind, or rain.>Stick to simple terrain and be aware of what is above you at all times.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Very Likely

Expected Size

1 - 5

Persistent Slabs

Primarily a concern in Northern sections. A buried surface hoar layer in the middle of the snowpack could be triggered by additional loading from snow or wind or by the weight of a rider. Also, a weak facet/crust combo lurks near the ground.

Be aware of the potential for large, deep avalanches due to the presence of buried weak layers.>Avoid shallow snowpack areas where triggering is more likely.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible

Expected Size

2 - 5

Valid until: Jan 2nd, 2014 2:00PM