Avalanche Forecast

Issued: Nov 23rd, 2013 8:23AM

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

bcorrigan, Avalanche Canada

South Columbia.

Forecast produced with limited field observations. If you're in the field, please send any information to:forecaster@avalanche.ca

Summary

Confidence

Fair - Due to the number and quality of field observations

Weather Forecast

Cool temps will give way to gradual warming for the forecast period with freezing levels going up to 3000 M in the next few days. No significant precipitation is in the forecast for the next 7 days. Winds are expected to be generally light to moderate for the forecast period.

Avalanche Summary

High winds accompanying the last significant snowfall produced wind slabs in exposed alpine and tree line locations producing avalanches up to size 3. Rising temps may produce wet sloughs on steep S facing alpine slopes and could trigger deeper instabilities

Snowpack Summary

Recent storm snow is settling and will gain strength with time and warming temps. Wind slabs linger in lee terrain. Surface hoar buried in early November exists in the mid snowpack but due to a lack of data little is known about its reactivity. The October crust/facet interface buried in the lower snowpack will likely be of concern for the foreseeable future. Valley fog and cold clear temps are producing a new surface hoar layer at fog levels and in sheltered north aspects.

Problems

Wind Slabs

Wind slabs persist in the alpine and at tree line especially on lee slopes

Be cautious as you transition into wind affected terrain.>Be aware of the potential for wide propagations due to the presence of hard windslabs.>

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

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

2 - 4

Persistent Slabs

A crust layer buried near the base of the snowpack will remain problematic for some time to come, with the possibility of producing large and destructive avalanches.

Dig down to find and test weak layers before committing to a line.>Be aware of the potential for full depth avalanches due to deeply buried weak layers.>

Aspects: All aspects.

Elevations: Alpine.

Likelihood

Possible

Expected Size

1 - 5

Loose Wet

Rising temperatures can produce wet sloughs on southerly aspects and may trigger deeper instabilities

Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.>Avoid steep Southerly aspects.>

Aspects: North, North East, East.

Elevations: Alpine, Treeline.

Likelihood

Possible - Likely

Expected Size

1 - 4

Valid until: Nov 24th, 2013 2:00PM