Archived

Avalanche Forecast

Dec 22nd, 2012–Dec 23rd, 2012

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

2: Moderate

The avalanche danger rating below treeline will be moderate

Alpine

2: Moderate

The avalanche danger rating in the alpine will be moderate

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Alpine

3: Considerable

The avalanche danger rating in the alpine will be considerable

Treeline

2: Moderate

The avalanche danger rating at treeline will be moderate

Below Treeline

1: Low

The avalanche danger rating below treeline will be low

Regions: Sea To Sky.

Avalanche danger ratings are based on light to locally moderate accumulations on Saturday night. If snowfall amounts are higher, the danger rating will increase.

Confidence

Poor - Forecast snowfall amounts are uncertain on Sunday

Weather Forecast

Sunday: Light to locally moderate snowfall on Saturday night should ease to light snowfall by Sunday / Moderate southeast winds / Freezing level at 900mMonday: Mostly clear skies / Light southeast winds / Freezing level at 900mTuesday: moderate snowfall / Light southeast winds / Freezing level at 600mConfidence: Good for the overall pattern / Poor for specific snowfall amounts on Saturday night/ Sunday morning

Avalanche Summary

Explosives control on Friday produced storm/windslab avalanches to size 2. I would suspect ongoing new snow avalanche activity on Sunday if snowfall/winds are moderate or higher.

Snowpack Summary

The region has received an impressive amount of new snow in recent days with over a metre falling throughout the week in some areas. The snowfall was accompanied by consistently strong to extreme winds that have since backed off leaving windslabs at higher elevations and deep loose snow below treeline.A couple of layers of surface hoar were buried last week in some areas. Another deeper layer of surface hoar from late November is now well over a metre down. No activity has been reported on any of these surface hoar layers. In general, the mid-pack is reported to be well settled and strong. The early November crust/facet combination near the base of the snowpack seems to be dormant; however, the consequences of a deep release would be very serious. Avalanches at this interface would most likely require a large trigger along a thin, unsupported snowpack area.

Avalanche Problems

Storm Slabs

Moderate winds and new snow are likely to promote ongoing surface instabilities. Triggering will be most likely in wind-affected, upper elevation terrain. In sheltered areas, watch for sluffing in steep terrain.

Be alert to conditions that change with elevation.>Be cautious as you transition into wind affected terrain.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood: Possible - Likely

Expected Size: 1 - 3