Avalog Join
Archived

Avalanche Forecast

Apr 18th, 2013–Apr 19th, 2013
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
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
2: Moderate
The avalanche danger rating in the alpine will be moderate
Treeline
1: Low
The avalanche danger rating at treeline will be low
Below Treeline
1: Low
The avalanche danger rating below treeline will be low

Regions: Sea To Sky.

Confidence

Fair - Forecast snowfall amounts are uncertain on Thursday

Weather Forecast

Thursday night and Friday: Light snowfall (higher amounts are more likely in the South end of the region) / Moderate southwest winds becoming light on Friday / Freezing levels at about 1500mSaturday: Cloudy with isolated flurries / Moderate west winds / Freezing level at 1500mSunday: Ridging will develop resulting in clearing skies and rising freezing levels

Avalanche Summary

Recent avalanches have been limited to loose wet sluff to size 1.5.

Snowpack Summary

North and Northeast aspects above 2000m continue to hold up to 20cm of dry snow, otherwise,  the surface condition is crusts. The carrying strength of the crusts vary depending on aspect and elevation as well as proximity to rocks, etc.... Generally speaking, the crusts have been going moist in the afternoon and then refreezing at night in all but the lowest terrain. Immediate lee features in the high alpine hold isolated softslabs that may still be reactive to rider triggering. Planar results have been observed in sheltered start zones. In some places outflow winds have reverse loaded pockets of the most recent storm snow onto the melt freeze surfaces of south facing slopes, creating small, reactive slabs in unusual places.In the upper snowpack (down 50-70cm) a significant melt-freeze crust lingers. Some facetting has been observed above and below this crust. At the same interface spotty surface hoar may linger on high, sheltered north facing terrain. There has been no recent stability test results on this layer.Cornices are huge and will continue to grow with the forecasted precipitation.

Avalanche Problems

Wind Slabs

New softslabs will likely build with forecasted precipitation.  Old windslabs linger and some previous reverse loading has occurred. Concern remains for step downs to isolated surface hoar on sheltered, high north facing slopes.
Stay off recent wind loaded areas until the slope has had a chance to stabilize.>Avoid travelling in areas that have been reverse loaded by winds.>

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

Elevations: Alpine, Treeline.

Likelihood: Likely

Expected Size: 1 - 3

Cornices

Cornices are gigantic and may become weaker with additional wind and snow.
Pay attention to overhead hazards like cornices.>Give cornices a wide berth when travelling on or below ridges.>

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

Elevations: Alpine.

Likelihood: Unlikely - Possible

Expected Size: 2 - 6