Avalanche Forecast

Issued: Jan 6th, 2017 4:42PM

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

Avalanche Canada mgrist, Avalanche Canada

Be cautious in areas with thin snowpacks, especially shallow rocky spots. A fresh round of windslabs may be lurking near ridge crests.

Summary

Confidence

Moderate - Due to the number of field observations

Weather Forecast

We've had a bit of a shift from the very cold conditions, and temperatures have warmed by 5 - 10 degrees Celcius. Only some isolated flurries are possible until late Sunday, when a small amount (5-10 cms) of light dry snow is forecast.SATURDAY: Sunny breaks with increasing clouds overnight. Flurries overnight with little accumulation. Winds light southerly. Alpine highs to -13 Celcius.SUNDAY: Cloudy with sunny breaks. Winds light southerly. Alpine temperatures between -15 and -20 Celcius; 5-10 cms light dry snow overnight.MONDAY: An additional 5-10 cms light dry snow are possible during the day and overnight. Winds light - moderate southwesterly. Alpine temperatures steady near -14 to -18 Celcius.

Avalanche Summary

No new avalanches observed.

Snowpack Summary

Another round of moderate northerly winds has moved through the Crowsnest pass and northern areas in the past 24 hours, causing fresh wind slabs on south and west aspects. In some areas these wind slabs may be sitting on an old scoured surface that was stripped by previous strong westerly winds that developed wind slabs on north and east aspects. The newer wind slabs are probably easier to trigger, but the old wind slabs may continue to release with the added load of a rider, especially where they are sitting on a shallow weak sugary base. The mid snowpack is generally right side up, with the mid-December interface down 40-80cms, giving inconsistent results in snowpack tests. There is some faceting below this interface but resistances are good and showing signs of rounding (stabilizing). Travel conditions have been challenging (especially at lower elevations) and little change is expected until a significant warm up helps to settle the snowpack.

Problems

Wind Slabs

An icon showing Wind Slabs
Recent strong winds have been from several directions, creating wind slabs and reverse loading. Expect these wind slabs to continue to be easy to trigger, and may take longer than usual to settle and bond due to the cold temperatures
If triggered the wind slabs may step down to deeper layers resulting in large avalanches.Be cautious as you transition into wind affected terrain.Avoid travelling in areas that have been reverse loaded by winds.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Possible

Expected Size

1 - 2

Persistent Slabs

An icon showing Persistent Slabs
Where denser snow overlies weak, sugary snow, there is the potential to trigger large, dangerous avalanches. Dig down and test for weak layers before committing to any steep slope.
Be aware of the potential for full depth avalanches due to deeply buried weak layers.Danger spots are where denser snow overlies weak, sugary snow below.Watch for whumpfing, hollow sounds, shooting cracks or recent avalanches.

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

2 - 3

Valid until: Jan 7th, 2017 2:00PM